A tennis ball is thrown at a wall and then bounces off.
Which row states the correct directions for the velocity, v, before and after hitting the wall?
Before collision |
After collision |
|
A. | − | − |
B. | − | + |
C. | + | − |
D. | + | + |
A car drives into a wall. The change in momentum is 17 000 kg ms−1 and the time of impact is 0.1 seconds.
What is the force acting on the car as a result of the collision?
17 000 N
1 700 000 N
170 000 N
1700 N
Which feature on a force-time graph represents the impulse?
Gradient
y-intercept
Area
x-intercept
Before a collision object A is stationary and object B is travelling at 1 ms−1 .
What is the correct symbol and value for the initial velocity of object A?
uB = 0
uA = 0
vA = 0
uA = 1
What is the definition of an external force?
Forces that act on a system from outside of it
Forces exchanged by the particles in a system
Every action has an equal and opposite reaction
The rate of change of momentum on a body
What is the definition of an inelastic collision?
A collision where kinetic energy is conserved
A collision where the momentum is conserved
A collision where both objects are stationary after the collision
A collision where kinetic energy is not conserved
What is the main purpose of the crumple zone in a car?
To decrease the contact time over which a collision occurs.
To increase the contact time over which a collision occurs.
To reduce the mass of the car involved in the collision.
To reduce damage to the rest of the car in a collision.
What type of collision are explosions?
Elastic
Conserved
Inelastic
Impulsive