Reading Quiz 10 (CH 7-7.7)
Two cars are approaching each other, one traveling north with a momentum of 3 kg-m/s and one traveling east with a momentum of 4 kg-m/s. The two cars collide and stick together. Right after the collision (choose all that apply) - the eastern component of the momentum of the two cars is 4 kg-m/s. - the northern component of the momentum of the two cars is 3 kg-m/s. - the total momentum of the two cars is 7 kg-m/s
- the eastern component of the momentum of the two cars is 4 kg-m/s. - the northern component of the momentum of the two cars is 3 kg-m/s.
Which variable is in the equation that relates force to transfer of energy (work)? - displacement - velocity - acceleration - time
Displacement
Two objects, each with a mass of 1 kg, are each moving 1 m/s. One object is moving east and one object is moving north. The total momentum of the two objects is 2 kg m/s.
False
Consider a system of objects that collide with no external forces acting on the systerm. Which of the following is correct for the system? Select all that apply. - For all collisions in the system, momentum is conserved. - For all collisions in the system, kinetic energy is conserved. - For elastic collisions in the system, momentum is conserved. - For elastic collisions in the system, kinetic energy is conserved.
For all collisions in the system, momentum is conserved. For all elastic collisions in the system, momentum is conserved. For all elastic collisions in the system, kinetic energy is conserved.
The concepts of momentum and impulse are most useful in describing - situations where objects have a change in potential energy. - situations in which objects are moving in circular paths. - situations that involve gradual changes in speed. - situations like collisions where there are powerful brief forces.
Situations like collisions where there are powerful brief forces
Which of the following is true? (Select all that apply). - The total momentum of the universe is conserved in any process. - Regardless of how you define the system, the total momentum of that system will be conserved in any collision. - The total momentum of an object is conserved in any process. - The total momentum of a system is conserved when there is no net external force on the system.
The total momentum of the universe is conserved in any process, the total momentum of a system is conserved when there is no net external force on the system
In a completely inelastic collision the colliding objects stick together and kinetic energy is not conserved.
True
In an inelastic collision momentum is conserved but kinetic energy is not conserved.
True
Is linear momentum a scalar or a vector?
Vector
Which variable is in the equation that relates force to the change in momentum? - displacement - velocity - acceleration - time
time
Kinetic energy is related to momentum by the equation K = p^2/(2m)
true
When an impulse is applied to the object, what will always happen to the object? - It will speed up. - It will slow down. - It's momentum will change. - It's kinetic energy will change.
Its momentum will change
An object is moving north with a velocity of 10 m/s. What is the direction of linear momentum of the object. - South - North - East - West - Momentum doesn't have a direction - Not enough information is given to know the direction
North