Practice for Physics Final Exam - Semester 2 2022

Given a car traveling 8 m/s heading west. Suppose one of your friends is not certain how speed is different from velocity. Which is the best answer of the four to CLARIFY to your friend?

• speed is west velocity is 8 m/s

• speed is "8 m/s " without reference to direction. However, velocity is the speed with reference to the direction which is "8 m/s heading west"

• speed includes the direction and velocity excludes the direction

Which formula for calculating the force based on Newton's Second Law involving the mass of an object and its acceleration?

• 480 Newtons

• 48 Newton

• 0.48 Newtons

• 0.048 Newtons

Which of the following is FALSE about UNIFORM CIRCULAR Motion (UCM)?

• The direction of the velocity changes.

• The accceleration is directed inwards toward the center of the circular path.

• The speed (the magnitude of the velocity with NO reference to direction) changes.

• The object is accelerating due to the change in the direction of the velocity.

For an objects traveling in a circular path:

Why do objects experience centripetal acceleration even though they can have a constant speed? (Hint: refer to given diagram)

• because they are constantly changing direction and hence, velocity changes, and that net change is directed inward.

• because they are speeding up as the move in a circle

• because they are constantly changing both direction and speed (speed is the numerical value or magnitude of velocity)

• because the direction of the force is outward

If an object is spinning around on a string and the string was suddenly cut, the object would move in what type of path?

• a jagged path

• a curved path

• a straight line , tangent to the edge

• a straight line, heading towards the center (of the circular path of the string)

When an object is moving in a circle, its LINEAR velocity is called its ____________ velocity. (Hint look at the green vectors)

• centripetal

• gravitational

• centrifugal

• tangential

Which of the following depict the acceleration and the tangential velocity of the object traveling in uniform circular motion?

• D = acceleration

  B = tangential velocity

• A = acceleration

  C= tangential velocity

• A = acceleration

  D = tangential velocity

• D= acceleration

  C= tangential velocity

The velocity is always _______ to the line of a circle.

• outwards

• tangent

• towards the center

• perpendicular

What is the formula for centripetal acceleration (points inward) of an object traveling with velocity "v" in a circle of radius "r"?