Semester I Exam

Full Name

Which of the following forces arises from direct physical contact between two objects?

• a. gravitational force
• b. fundamental force
• c. contact force
• d. field force

When velocity is negative and acceleration is negative, what happens to the object’s motion?

• The object slows down.
• The object speeds up.
• Nothing happens to the object.
• The object remains at rest.

The baseball catcher throws a ball vertically upward and catches it in the same spot as it returns to the mitt. At what point in the ball’s path does it experience zero velocity and nonzero acceleration at the same time?

• midway on the way up
• at the top of its trajectory
• the instant it leaves the catcher’s hand
• the instant before it arrives in the catcher’s mitt

A sports car accelerates at a constant rate from rest to a speed of 27.8 m/s in 8.00 s. What is the displacement of the sports car in this time interval?

• 55.0 m
• 77.0 m
• 111 m
• 222m

The Greek letter delta (Δ), indicates a(n)

• difference or change
• sum or total
• direct proportion
• inverse proportion

A hiker travels south along a straight path for 1.5 h with an average velocity of 1.75 km/h, then travels south for 2.5 h with an average velocity of 0.90 km/h. What is the hiker’s displacement for the total trip?

• 1.3 km to the south
• 3.5 km to the south
• 4.9 km to the south
• 5.3 km to the south

A tourist accidentally drops a camera from a 50.0 m high bridge. What is the speed of the camera as it hits the water?

• 0.0 m/s
• 9.81 m/s
• 31.3 m/s
• 981 m/s

What causes a moving object to change direction?

• a. acceleration
• b. velocity
• c. inertia
• d. force

A crate is pulled with a force directed 35.0 degrees above the horizontal. If the vertical component of the force on the suitcase is 60.6 N, what is the force exerted on the handle?

• 74 N
• 70 N
• 106 N
• 96 N