Answer:
-2200 N
Explanation:
The change in momentum of Sarah is equal to the impulse, which is the product between the force exerted by the seatbelt on Sarah and the time during which the force is applied:
where
m is the mass
is the change in velocity
F is the average force
is the duration of the collision
In this problem:, we have:
m = 55 kg is Sarah's mass
is the change in velocity
is the duration of the collision
Solving for F, we find the force exerted by the seatbelt on Sarah:
Where the negative sign indicates that the direction of the force is opposite to that of Sarah's initial velocity.
Answer:
h = 3.5 m
Explanation:
First, we will calculate the final speed of the ball when it collides with a seesaw. Using the third equation of motion:

where,
g = acceleration due to gravity = 9.81 m/s²
h = height = 3.5 m
vf = final speed = ?
vi = initial speed = 0 m/s
Therefore,

Now, we will apply the law of conservation of momentum:

where,
m₁ = mass of colliding ball = 3.6 kg
m₂ = mass of ball on the other end = 3.6 kg
v₁ = vf = final velocity of ball while collision = 8.3 m/s
v₂ = vi = initial velocity of other end ball = ?
Therefore,

Now, we again use the third equation of motion for the upward motion of the ball:

where,
g = acceleration due to gravity = -9.81 m/s² (negative for upward motion)
h = height = ?
vf = final speed = 0 m/s
vi = initial speed = 8.3 m/s
Therefore,

<u>h = 3.5 m</u>
Answer : The kinetic energy depends directly on the mass of a particle.
Explanation :
We know that the kinetic energy of any particle is given by :

Where,
m is the mass of an object.
v is the velocity with which it is moving
Kinetic energy is due to the motion of the particle.
So, the kinetic energy of a particle is directly proportional to its mass.
Hence, the conclusion of the question is if the mass of a particle is increases then its kinetic energy also increase.