Quarter Two Physics MCA

Multiple Choice

Identify the letter of the choice that best completes the statement or answers the question.

____1.Which of Newton’s laws best explains why motorists should buckle-up?

a. / The law of inertia / c. / The third law
b. / Law of acceleration / d. / the lw of gravitation

____2.A constant net force acts on a object. Describe the motion of the object.

a. / constant acceleration / c. / constant velocity
b. / constant speed / d. / increasing acceleration

____3.The acceleration of an object is inversely proprtional to

a. / the net force acting on it / c. / its velocity
b. / its position / d. / its mass

____4.If you blow-up a balloon, and then release it, the balloon will fly away. This is an illustration of

a. / Law of acceleration / c. / Second law
b. / Law of inertia / d. / Third Law

____5.A golf club hits a golf ball with a force of 2400N. The golf ball hits the club face with a force

a. / slightly less than 2400 N / c. / Slightly more than 2400 N
b. / exactly 2400 N / d. / close to 0 N

____6.A child’s toy is suspended from the ceiling by means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the “action force,” what is the “reaction force”?

a. / The string pulling upward on the toy with an 8.0 N force / c. / The string pulling downward on the ceiling with an 8.0 N force
b. / The ceiling pulling upward on the string with an 8.0 N force / d. / The toy pulling upward on the Earth with an 8.0 N force

____7.Two cars collide head-on. At every moment during the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitude of the force the second car exerts on the first. This is an example of

a. / Newton’s First law / c. / Law of Gravitation
b. / Newton’s Second law / d. / Newton’s Third law

____8.Action -reatcion forces are

a. / equal in magnitude and point in the same direction / c. / unequal in magnitude but point in the same direction
b. / equal in magnitude but point in opposite directions / d. / unequal in magnitude but point in opposite directions

____9.Mass and weight

a. / both measure the same thing / c. / both mass and weight are less
b. / mass is the same, weight is less / d. / both mass and weight are the same

____10.An example of a force that acts at a distance is

a. / tension / c. / static friction
b. / weight / d. / kinetic friction

____11.A stone is thrown straight up. At the top of its path, the net force acting on it is

a. / greater than its weight / c. / instantaneously equal to zero
b. / greater than zero, but less than its weight / d. / equal to its weight

____12.An object of mass m is hanging by a string from the ceiling of an elevator. The elevator is moving up at a constant speed. What is the tension in the string?

a. / less than a mg / c. / greater than mg
b. / exactly mg / d. / cannot be determined without knowing speed

____13.The force that keeps you from sliding on an icy sidewalk is

a. / weight / c. / static friction
b. / kinetic friction / d. / normal force

____14.A block of mass M slides down a frictionless plane at an angle  to the horizontal. The normal reaction force exerted by the plane on the block is

a. / Mg / c. / Mg cos 
b. / Mg sin / d. / zero, due to the frictionless plane

____15.If you push twice as hard against a stationary brick wall, the amount of work you do

a. / doubles / c. / remains constant but non-zero
b. / is cut in half / d. / remains constant at zero

____16.If you walk 5.0 m horizontaly forward at a constant velocity carrying a 10 N object, the amount of work you do is

a. / more than 50 J / c. / less than 50 J, but more than 0 J
b. / equal to 50 J / d. / zero

____17.A container of water is lifted vertically 3.0m then returned to its original position. If the total weight is 30 N, how much work was done?

a. / 45 J / c. / 180 J
b. / 90 J / d. / no work was done

____18.The area under the curve, on a Force versus Position graph, represents

a. / work / c. / power
b. / kinetic energy / d. / potential energy

____19.The quantity mgy is

a. / the kinetic energy of an object / c. / the work done on the object by the force
b. / the gravitational potential energy of an object / d. / the power supplied to the object by the force

____20.The quantity 1/2 kx2 is

a. / the kinetic energy of the object / c. / the work done on the object by the force
b. / the elastic potential energy of the object / d. / the power supplied to the object by the force

____21.The total mecahnical energy of a system

a. / is equally divided between kinetic and potential energy / c. / can never be negative
b. / is either all kinetic or all potential energy, at any one instant / d. / is constant, only if conservative forces act

____22.An acorn falls from a tree. Cfompare its kinetic energy K,to its potential energyU.

a. / K increases and U decreases / c. / K increases and U increases
b. / K decreases and U decreases / d. / K decreases and U increases

____23.A ball falls from the top of a building, through the air (air friction is present), to the ground below. How does the kinetic energy K just before striking the ground compare to the potential energy U at the top of the building?

a. / K is equal to U / c. / K is less than U
b. / K is greater than U / d. / It is impossible to determine

____24.The quantity Fd/t is

a. / the kinetic energy of the object / c. / the work done on the object by the force
b. / the potential energy of the object / d. / the power supplied to the object by the force

____25.To accelerate your car at a constant acceleration, the car’s engine must

a. / maintain a constant power output / c. / develop ever-increasing power
b. / develop ever-decreasing power / d. / maintain a constant turning speed

____26.When a cannon fires a cannonball, the cannon wil recoil backward because the

a. / energy of the cannonball and cannon is consereved / c. / energy of the cannon is greater than the energy of the cannonball
b. / momentum of the cannon and cannonball is conserved / d. / momentum of the cannon is greater than the momentum of the cannonball

____27.A freight car moves along a frictionless lwvel railroad track at a constant speed. The car is open on top. A large load of coal is suddenly dumped into the car. What happens to the velocity of the car?

a. / it increases / c. / it decreases
b. / it remains the same / d. / can not be determined based on the information

____28.The area under the curve on a Force versus Time graph, represents

a. / impulse / c. / work
b. / momentum / d. / kinetic energy

____29.A small car meshes with a alrge truck in a head-on collision. Which of the following statements concerning the magnitude of the average collision force is correct?

a. / the truck experiences the greater average force / c. / the small car and the truck experience the same average force
b. / the small car experiences the greater average force / d. / it is impossible to tell since the masses and velocities are not given

____30.Two objects collide and bounce off each other. Linear momentum

a. / is definitely conserved / c. / is conserved only if the collision is elastic
b. / is definitely not conserved / d. / is conserved only if the environment is frictionless

____31.When is kinetic energy conserved

a. / in elastic collisions / c. / in any collision in which the objects do not stick together
b. / in elastic collisions / d. / in all collisions

____32.In a game of pool, the white cue ball hits the #5 ball and stops, while the #5 ball moves away with the same velocity as the cue ball had originally. The type of collsion is

a.elastic b.inelastic c.completely inelastic d.impusle

____33.A rubber ball with a speed of 5.0m/s collides head-on elastically with an identical ball at rest. What is the speed of the initially stopped ball after the collision?

a. / 0.0 m/s / c. / 2.5 m/s
b. / 1.0 m/s / d. / 5.0 m/

____34.A very heavy object with speed v collides head-on with a very light object at rest. The collision is elastic, and there is no friction. The heavy object barely slows down. What is the speed of the light object after the collision?

a. / nearly v / c. / nearly 3v
b. / nearly 2v / d. / infinite

____35.A very light object moving with a speed v collides head-on with a very heavy object at rest, in a frictionless environment. The collision is almost perfectly elastic. The speed of the heavy object after the collision is

a. / slightly greater than v / c. / slightly less than v
b. / equal to v / d. / much less than v

____36.In an inelastic collision, if the momentum is conserved, then which of the following statements is true about kinetic energy?

a. / kinetic energy is also conserved / c. / kinetic energy is lost
b. / kinetic energy is gained / d. / kinetic energy is not involved

____37.A small object collides with a large object and sticks. Which object experiences the larger magnitude of momentum change?

a. / the large object / c. / both objects experiencve the same change
b. / the small object / d. / can not be determined from the information given

____38.In a game of pool, the white ball hits the #9 ball and is deflected at an angle of 35o angle to the original line of motion. What is the angle of deflection below the original line of motion for the #9 ball?

a. / 35 degrees / c. / 75 degrees
b. / 55 degrees / d. / 90 degrees

____39.A plane, flying horizontally, releases a bomb, which explodes before hitting the ground. Neglecting air resistance, the center of mass of the bomb fragments, just after the explosion

a. / is zero / c. / moves vertically
b. / moves horizontally / d. / moves along a parabolic path

____40.If the net work done on an object is negative, then the object’s kinetic energy

a. / decreases / c. / increases
b. / remains the same / d. / is zero

____41.Which one of the following is an example of a vector quantity?

a. / distance / c. / mass
b. / velocity / d. / area

____42.Ignoring air resistance, the horizontal component of a projectile’s acceleration

a. / is zero / c. / increases
b. / remains a non-zero constant / d. / decreases

____43.Ignoring air resistance, the horizontal component of a projectile’s velocity

a. / is zero / c. / increases
b. / remains constant / d. / decreases

____44.When a football in a field goal attempt reaches its maximum height, how does its speed compare to its initial speed?

a. / it is zero / c. / it is equal to the inital speed
b. / it is less than the original speed / d. / it is greater than the initial speed

____45.A plane drops a bomb from a plane flying horizontally at a constant speed. Neglecting air resistance, when the bomb hits the ground the horizontal location of the plane will

a. / be behind the bomb / c. / be in front of the bomb
b. / be over the bomb / d. / depends on the speed of the plane when the bomb was released

____46.If the acceleration of an object is alwaysdirected perpindicular to its velocity,

a. / the object is speeding up / c. / the object is turning
b. / the object is slowing down / d. / the situation is not possible

____47.If the net work done on an object is negative, then the object’s kinetic energy

a. / decreases / c. / increases
b. / remains the same / d. / is zero

____48.Is it possible for a system to have negative potential energy?

a. / Yes, as long as the total energy is positive / c. / No, because the kinetic energy of a system must equal its potential energy
b. / Yes since the choice of the zero of potential energy is arbitrary / d. / No, because this would have no physical meaning

____49.Describe the energy of a car driving up a hill

a. / entirely kinetic / c. / both kinetic and potential
b. / entirely potential / d. / gravitational

____50.Action - reaction forces

a. / sometimes act on the same object / c. / may be at right angles
b. / always act on the same object / d. / always act on different objects