11.M2.MCQ Conceptual

Two men are having a shoving contest, each man pushes the other at the exact same time. Ross pushes Jake with 90.4N of force and Jake pushes Ross with 110.2N of force. How much force is exerted on Jake?

• 19.8 N

• 200.6 N

• 110.2 N

• 180.8 N

Two football players are pushing on each other during a play. The offensive player is pushing the defensive player backwards. What can be said about the forces in this situation?

• The players are exerting equal forces on each other, however, the offensive player is exerting more force on the ground that the defensive player.

• The players are exerting unequal forces on each other because the offensive player is exerting more force on the ground that the defensive player.

• None of these

• It is impossible to determine anything without knowing the mass of each player.

• The players are exerting unequal forces on each other, the offensive player is exerting more force on the defensive player.

A 2000kg car with a velocity of v collides head on with a 6000kg truck with a velocity of −v. Which vehicle experiences the greater force? Which experiences the greater acceleration?

• The truck experiences the greater force and the car experiences the greater acceleration

• The truck experiences the greater force and the greater acceleration

• Both the car and the truck experience equal force and acceleration

• The car experiences the greater force and the greater acceleration

• The car and the truck experience equal force and the car experiences greater acceleration

In which of the following situations can we claim the net force is zero on the object described?

• A child swinging on a swing set.

• A bird taking flight from the ground.

• Airplane changing direction to avoid a storm while maintaining a constant speed.

• Car breaking to a stop.

• Elevator ascending at a constant speed.

A car of mass m is driving around a circular track of radius r at a constant velocity of v. The centripetal force acting on the car is Fc. If the car's velocity is doubled, what is the new centripetal force required for the car to drive on the circular track?

• 2Fc

• 4Fc

• Fc^2

• Fc/2

• Fc

Imagine a car driving over a hill at a constant speed. Once the car has reached the apex of the hill, what is the direction of the acceleration?

• in the direction of motion

• upwards

• downwards

• no acceleration

• opposite the direction of motion

A bodybuilder is in the midst of a an intense training session. He is currently bench pressing a bar with a mass of 250kg. If he does six reps of this mass and his arms are 0.75m long, how much work has been done on the bar between the time the bar was removed from its rack and placed back on the rack?

• 0 J

• 1225 J

• None of the other answers here

• 510 J

• 1875 J

The work done by a centripetal force on an object moving in a circle at constant speed is __________.

• zero

• equal to the kinetic energy of the object

• equal to the force exerted

• equal to the force exerted multiplied by the displacement

Conservation of energy is true for what case?

• If there are no forces external forces acting on the system

• When there are no non-conservative forces F,nc acting

• When the direction of the force is perpendicular to the motion

• Conservation of energy is always true regardless of the defined system

Which of the following explains why when we land on our feet, it's a good idea to bend our knees?

• By bending our knees we use less force to stop, which makes the impulse smaller

• By bending our knees we extend the time it takes us to stop, which increases the impact force

• When we bend our knees we extend the time in which we apply the force that stops us, so our impulse is greater

• When we bend our knees we extend the time in which we apply the force that stops us, so our impulse is smaller

• By bending our knees we extend the time it takes us to stop, which diminishes the impact force