Answer:
gravity pulls down on student the chair pushes up on the student's body with the same force gravity is pulling down on the student
A ray of light strikes a flat mirror at an angle of 40° from the perpendicular. The light is reflected at
what opposite angle to the same perpendicular line?
a) 40°
b) 50°
c) 30°
d) 60°
Answer:
a
Explanation:
angle of incidence equals angle of reflection on flat surface
Answer:
40 degress
Explanation:
A 1000 kg truck moving at 2.0 m/s runs into a concrete wall. It takes 0.5 s for the truck to completely stop. What is the magnitude of force exerted on the truck during the collision?
Answer:
Momentum is given by
p
=
m
v
. Impulse is the change of momentum,
I
=
Δ
p
and is also equal to force times time:
I
=
F
t
. Rearranging,
F
=
I
t
=
Δ
p
t
=
0
−
20
,
000
5
=
−
4000
N
.
Explanation:
Momentum before the collision is
p
=
m
v
=
2000
⋅
10
=
20
,
000
k
g
m
s
−
1
.
Assuming the truck comes to a complete halt, the momentum after the collision is
0
k
g
m
s
−
1
.
The change in momentum,
Δ
p
, is initial minus final
→
0
−
20
,
000
=
−
20
,
000
This is called the impulse:
I
=
Δ
p
. Impulse is also equal (check the units) to force times time:
I
=
F
t
.
We can rearrange this expression to make
F
the subject:
F
=
I
t
=
Δ
p
t
=
−
20
,
000
5
=
−
4000
N
The negative sign just means the force acting is in the opposite direction to the initial momentum.
(This will be the average force acting during the collision: collisions are chaotic so the force is unlikely to be constant.)
What is the magnitude of the electric field at the point (8.70 - 9.10 7.20 ) m if the electric potential is given by V
This question is incomplete, the complete question is;
What is the magnitude of the electric field at the point (8.70i - 9.10j + 7.20k ) m if the electric potential is given by V = 4.30xyz², where V is in volts and x, y and z are in meters.
Answer:
the magnitude of the electric field is 5648.67 N/C
Explanation:
Given the data in the question;
Suppose electric field at this point is;
E = Exi + Eyj + Ezk
Now, electric field is given by;
E = -dV/dr
so,
Ex = -d( 4.30xyz² )/dx = -4.30yz²
Ey = -d( 4.30xyz² )/dy = -4.30xz²
Ez = -d( 4.30xyz² )/dz = -8.60xyz
so
E = -4.30yz² i - 4.30xz² j - 8.60xyz k
now, at the point (8.70i - 9.10j + 7.20k )
E = (-4.30(-9.10)(7.20)²) i + (-4.30(8.70)(7.20)²) j + (-8.60(8.70)(-9.10)(7.20) k
E = 2028.499 i - 1939.334 j + 4902.206 k
so, Magnitude of electric field will be;
|E| = √( Ex² + Ey² + Ez² )
we substitute
|E| = √( (2028.499)² + (-1939.334)² + (4902.206)² )
|E| = √( 31907448.222993 )
|E| = 5648.67 N/C
Therefore, the magnitude of the electric field is 5648.67 N/C
What occurs as a ray of light passes from
al inilo water?
Answer:
this may be wrong but I am not sure
What happens when a moving object is moving a particular direction experiences a net force opposite the direction?
Answer:
stop
Explanation:
object stop
Answer:
If two forces of equal strength act on an object in opposite directions, the forces will cancel, resulting in a net force of zero and no movement. Two or more opposite forces are balanced forces if their effects cancel each other and they do not cause a change in an object's motion.
The following problem applies to questions 8 and 9: a glass window acquires a net negative charge on its surface after being cleaned. Particles of dust, which are usually charged positively, start accelerating toward the window. If a particle travels a distance of 1 meter before reaching the window, in a time duration of 10 sec, and if the mass of the particle is 1 micro-gram and the charge on the particle is 10-12 Coulomb, then the magnitude of the electric field intensity is Group of answer choices
Answer:
the magnitude of the electric field intensity is 20 N/C
Explanation:
Given the data in the question;
mass m = 1 micro gram = 1 × 10⁻⁹ kg
time duration t = 10 sec
distance s = 1 m
the charge on the particle q = 10⁻¹² Coulomb
force applied on a charged particle due to electric field E is;
F = Eq ------ equ 1
where q is the charge on the particle.
Also, force on a particle with mass m will be;
F = ma ------ equ
where a is acceleration
so F = ma = Eq
ma = Eq -------- equ 3
using kinetic equation
Distance = 1/2×at²
where a is acceleration and t is the time period
now lets consider that initial velocity is zero (0)
Here;
1 m = 1/2 × a × ( 10 s )²
1 m = a × 50 s²
a = 1 m / 50 s²
a = 0.02 m/s²
so, from equation 3
ma = Eq
E = ma / q
we substitute
E = (1 × 10⁻⁹ kg × 0.02) / 10⁻¹² Coulomb
E = 2 × 10⁻¹¹ / 10⁻¹²
E = 20 N/C
Therefore, the magnitude of the electric field intensity is 20 N/C
If a 15 N box is lifted a distance of 3 m, how much work is done?
0 J
45 J
5 J
5 N
Answer:
W=45J
Explanation:
W=Fd
W=15(3)=45
W=45J
what is the mass of a ball rolling at 4.5m/s if it's momentum is 3.5 kg•m/s?
Answer:
The ball has a mass of 7/9 kg
Explanation:
Momentum is just mass times velocity, so to find its mass, we can simply divide the given momentum by the given velocity.
[tex]3.5 kg\frac{m}{s} \div 4.5\frac{m}{s} = \frac{7}{9}kg[/tex]
An enormous thunderstorm covers Dallas-Ft. Worth. Your best friend Clark is a storm chaser and heads to the center of the storm to take some readings while you stay dry at home. While Clark is at the center of the storm, he sees and hears lightning strike a tree that is 190 m from where he is standing. You are 140 km from the tree. How long does it take for the sound to reach Clark
Answer:
407.61 seconds
Explanation:
Given that an enormous thunderstorm covers Dallas-Ft. Worth. Your best friend Clark is a storm chaser and heads to the center of the storm to take some readings while you stay dry at home. While Clark is at the center of the storm, he sees and hears lightning strike a tree that is 190 m from where he is standing. You are 140 km from the tree. How long does it take for the sound to reach Clark
Solution.
The distance between the Clark and you will be:
Distance = 140km - 190m
Distance = 140000 - 190
Distance = 139810 m
The radius of the earth is also considered but it will surely be insignificant as you subtracted the two distance values.
Using the formula
Speed = distance/time
Where
The speed of sound = 343 m/s
343 = 139810 / t
Make time the subject of formula
t = 139810 / 343
t = 407.61 s
Therefore, it will take 407.61 seconds for the sound to reach Clark
list the 5 components of fitness
What might Earth be like if it had never been hit by the theoretical protoplanet Orpheus?
Answer:
If Earth hadn't been hit by Orpheus, it would be covered by ocean, with perhaps a few mountaintops emerging through the water. There would be no humans, but there could be other forms of life. Earth would rotate rapidly, as the moon would not be present to produce the tidal friction that slows Earth's rotation today
Which one of the following statements concerning the buoyant force on an object submerged in a liquid is true?
A) The buoyant force depends on the mass of the object.
B) The buoyant force depends on the weight of the objeet.
C) The buoyant force is independent of the density of the liquid.
D) The buoyant force depends on the volume of the liquid displaced.
E) The buoyant force will increase with depth if the liquid is incompressible.
Answer:
D) The buoyant force depends on the volume of the liquid displaced.
Explanation:
Buoyancy can be defined as an upward force which is created by the water displaced by an object.
According to Archimede's principle, it is directly proportional to the amount (weight) of water that is being displaced by an object.
Thus, the greater the amount of water an object displaces; the greater is the force of buoyancy pushing the object up.
The buoyancy of an object is given by the formula;
[tex] Fb = pgV [/tex]
[tex] But, \; V = Ah [/tex]
[tex] Hence, \; Fb = pgAh [/tex]
Where;
Fb = buoyant force of a liquid acting on an object.g = acceleration due to gravity. p = density of the liquid.v = volume of the liquid displaced. h = height of liquid (water) displaced by an object. A = surface area of the floating object.The unit of measurement for buoyancy is Newton (N).
Additionally, the density of a fluid is directly proportional to the buoyant force acting on it i.e as the density of a liquid decreases, buoyancy decreases and vice-versa.
Hence, the statement concerning the buoyant force on an object submerged in a liquid which is true is that the buoyant force depends on the volume of the liquid displaced.
If an object is completely submerged, the volume of the object is equal to the volume of liquid displaced.
A student lifts her 15-kg backpack from the ground to her shoulder raising it 1.5 meters. Determine the work she does to life the backpack
A spring stretches 5 cm when a 300-N mass is suspended from it. Calculate the spring constant in N / m .
Answer:
Spring constant in N / m = 6,000
Explanation:
Given:
Length of spring stretches = 5 cm = 0.05 m
Force = 300 N
Find:
Spring constant in N / m
Computation:
Spring constant in N / m = Force/Distance
Spring constant in N / m = 300 / 0.05
Spring constant in N / m = 6,000
Two automobiles, each of mass 1000 kg, are moving at the same speed, 20 m/s, when they collide and stick together. In what direction and at what speed does the wreckage move (a) if one car was driving north and one south (b) if one car was driving north and one east?
A. The wreckage after collision is moving at the speed 18 m/s to the south.
B. The wreckage after collision is moving at the speed 9.0 m/s to the north.
C. The wreckage after collision is moving at the speed 9.0 m/s to the south.
D. The wreckage after collision is moving at the speed 18 m/s to the north.
E. The wreckage after collision is motionless.
Answer:
The reckage after collision is motionless (E)
Explanation:
The first law of thermodynamics states that energy is neither created nor destroyed but is converted from one form to another.
The kind of collision described in the question above is known as a perfectly inelastic collision, and in this type of collision, the maximum kinetic energy is lost because the objects moving in opposite directions have a resultant momentum that is equal, but in opposite directions hence they cancel each other out.
The calculation is as follows:
m₁v₁ + m₂v₂
where:
m₁ = m₂ = 1000kg
v₁ = 20 m/s
v₂ = -20 m/s ( in the opposite vector direction)
∴ resultant momentum = (1000 × 20) + (1000 × -20)
= 20000 - 20000 = 0
∴ The reckage after collision is motionless
Answer:
The wreckage after collision is moving at the speed 18 m/s to the south.
Explanation:
1. What is matter?
2. What are the three phases of matter?
3. Describe how gas particles move.
4. What is temperature?
5. The slower the particles, the ______________ the temperature.
6. A change in temperature causes what?
7. What is the difference between boiling and evaporation?
8. What is sublimation?
9. Name the three ways thermal energy is transferred.
10. Sunburn is an example of what?
11. Give an example of convection.
12. What is conduction?
13. What is the difference between conductors and insulators?
Answer:
1.matter is any substance that has mass and takes up space by having volume.
2.The three fundamental phases of matter are solid, liquid, and gas (vapour),
3.In gases the particles move rapidly in all directions, frequently colliding with each other and the side of the container. With an increase in temperature, the particles gain kinetic energy and move faster. ... In liquids, particles are quite close together and move with random motion throughout the container.
3.In gases the particles move rapidly in all directions, frequently colliding with each other and the side of the container. With an increase in temperature, the particles gain kinetic energy and move faster. ... In liquids, particles are quite close together and move with random motion throughout the container.
A car can go from 0 m/s to 27 m/s in 4.5 seconds. If a net force of 6600 N acted on the car, what is its mass? (Hint: You must first calculate the acceleration then plug into Newton’s second law.)
Answer:
1100 kg
Explanation:
acceleration:
[tex]a=(27-0)/4.5[/tex]
[tex]a=6ms^{-2}[/tex]
Newton's second law:
[tex]F=ma[/tex]
[tex]6600=6m\\m=1100 kg[/tex]
what's the difference between kinetic energy, potential energy, and mechanical energy?
Answer:
potential energy is stationary, with stored energy to be released; kinetic energy is energy in motion, actively using energy for movement.
Explanation:
https://taraenergy.com/blog/potential-and-kinetic-energy-explained/#:~:text=The%20main%20difference%20between%20potential,actively%20using%20energy%20for%20movement.
how many electrons can occupy each sublevel?
Why might video games increase creativity while the use of cell phones, the internet, or computers do not?
Explanation:
Video games are developed around a structure that is unique from your usual media, where there is a sense purpose in mind when playing a game, as decided by the player, and it allows them to explore creative options in order to solve scenarios, depending on the genre. In the use of phones, internet, or computers, this structure is more rare and diverse from video games, which does not lean more toward a creative purpose to build from. That idea gives people the inspiration and discover skills they never knew they even had.
4. Name three examples of "concentrated" forms of energy.
Answer:
Nuclear power plant.
Gas stove.
Dam.
Gas pump.
Geothermal heat pump.
Power lines.
Solar panels.
Windmills.
Explanation:
Hope this helps :))
Answer:
gasoline,solar panels,geothermal heat pump,windmills
Explanation:
[O.05]Which of these Earth spheres interact with oceans during beach erosion?
geosphere
hydrosphere
cryosphere
atmosphere
Answer:
hydrosphere of these Earth spheres interact with oceans during beach erosion.
Answer:
Geosphere
Explanation:
The geosphere is the solid parts of the earth including rocks, minerals, and sand on the beach. The shoreline is where the geosphere meets the ocean. This is how they interact during erosion.
It is not the hydrosphere because the ocean is a part of the hydrosphere.
A 50 kg mass is sitting on a frictionless surface. An unknown constant force called force A pushes the mass for 2 seconds until the mass reaches a velocity of 3 m/s. If the 50 kg mass is now pushed by an unknown force B and reaches the velocity of 3 m/s in 4 seconds, compare the impulse delivered to the mass when acted upon by force A with the impulse delivered to the mass when acted on by force B? *
A) The impulse delivered to the mass when acted upon by force A is greater
B) The impulse delivered to the mass when acted upon by force B is greater
C) The impulse is the same in each case
D) We need to know the value of force A and force B in order to determine this
Answer:
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
Can someone plz explain :
Two cars have the same mass, the first car is moving towards the east and the second is
stationary. If the two cars merge together after a collision and head towards the east their speed
after the collision is equal to.......
A)1/4vi b)1/2vi c)vi d) 2vi
Answer: Option b, the final velocity is half of the initial velocity.
Explanation:
Here we will use the conservation of the total momentum of a system.
This means that the total momentum at the beginning must be the same as the final momentum.
Where momentum is:
P = M*v
Initially, we have two cars, both with the same mass M, and only one of them has a velocity v.
Then the initial momentum is:
P = M*v + M*0 = M*v
After the collision, the two cars move together. Then the total mass that is moving is equal to the sum of the masses of the cars, this is 2*M
and we can suppose that the two cars move at a final velocity v'
Then the final momentum is:
P' = (2*M)*v'
Now we use the conservation of momentum, then:
P = P'
M*v = (2*M)*v'
Now we need to solve this for v'
(M*v)/(2*M) = v'
v/2 = v'
This means that the final velocity is half of the initial velocity.
Then the correct option is option b.
HELP me please cause I don't understand it.
Answer:
Force = 0.49 N (Approx)
Explanation:
Given:
Mass = 50 grams = 0.05 Kg
Acceleration = 9.81 m/s²
Find:
Force
Computation:
Force = Mass x Acceleration
Force = 0.05 x 9.81
Force = 0.4905
Force = 0.49 N (Approx)
A roller-coaster car has a mass of 1240 kg when fully loaded with passengers. As the car passes over the top of a circular hill of radius 22 m, its speed is not changing. (a) At the top of the hill, what is the normal force (using the negative sign for the downward direction) FN on the car from the track if the car's speed is v = 8.7 m/s? (b) What is FN if v = 20 m/s? Use g=9.81 m/s2.
Answer:
a) N = 7.90 10³ N, b) N = -1.04 10⁴ N
Explanation:
a) For this exercise we can use Newton's second law
N -W = m (-a)
The relationship is centripetal, the negative sign of the acceleration is because it points towards the center of the circle
a = v² / r
we substitute
N = mg -m v² /r
N = m (g - v² /r)
let's calculate
v = 8.7 m / s
N = 1240 (9.81 - 8.7²/22)
N = 7.90 10³ N
b) v = 20 m / s
N = 1240 (9.81 - 20²/22)
N = -1.04 10⁴ N
What is the difference in the speed of the generator with a small magnet and a generator with a large magnet?
Answer:
uADHTiszA?kv
Explanation:
A bug starts at point A, crawls 8.0 cm east, then 5.0 cm south, 3.0 west, and 4.0 cm north to point B.
Question:
How far north and east is B from A?
Find the displacement of the turtle from the origin at the point.
Answer:
5cm east& 1cm west from A
Explanation:
https://brainly.ph/question/2753392
The total distance travelled by bug is 19 cm while the displacement of the bug is 5.1 cm.
Given here,
A bug stat to crawl from point A
8 cm to east
5 cm to south
3.0 to west
4.0 cm north reach the point B,
Displacement:
It is the shortest distance between two point or the length of strait line between two points.
Therefore, the total distance travelled by bug is 19 cm while the displacement of the bug is 5.1 cm.
To know more about Displacement,
https://brainly.com/question/698931
what is tangential velocity
Answer:
Tangential velocity is the linear speed of any object moving along a circular path
Explanation:
Answer:
Tangential velocity is the linear speed of any object moving along a circular path. A point on the outside edge of a turntable moves a greater distance in one complete rotation than a point near to the center.
Explanation:
i hope this helps and can i get brainliest pls?
An airplane has a momentum of 8.55 x 107 kg.m/s[S] and a velocity of 900 km/h[S]. Determine the mass of the airplane.
95000kg is the mass of the airplane.
What is momentum?A property of a moving body that the body has by virtue of its mass and motion and that is equal to the product of the body's mass and velocity.
It is also known as the property of a moving body that determines the length of time required to bring it to rest when under the action of a constant force.
Mathematically ,
p = mv
According to the question,
Momentum of airplane = 8.55 x 10⁷ kg.m/s
Velocity of airplane = 900 km/h
Computing the values in the formula,
p = mv
8.55 x 10⁷ kg.m/s = m x 900 km/h
m =[tex]\frac{8.55 * 10^7 kg.m/s}{900 km/h}[/tex]
m = 95000 kg
Therefore ,
The mass of the airplane 95000 kg
Learn more about momentum here:
https://brainly.com/question/24030570
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