Question 1

A particle moves with a constant velocity of $$5\ \mathrm{m/s}$$ for $$10\ \mathrm{s}. $$What is its displacement during this time?

Accepted Answer

$$50\ \mathrm{m}$$

Question 2

Which of the following statements about the particle model is correct?

Accepted Answer

The particle model ignores the size and shape of the object.

Question 3

A car starts from rest and accelerates uniformly at $$2\ \mathrm{m/s^2$}$$ for $$4\ \mathrm{s}. $$What is its final velocity?

Accepted Answer

$$8\ \mathrm{m/s}$$

Question 4

Which kinematic equation would you use to find the displacement of an object when you know its initial velocity $$v_i$$, final velocity $$v_f$$, and time interval $$\Delta t$$?

Accepted Answer

$$x_f = x_i + \frac{1}{2}(v_i + v_f)\Delta t$$

Question 5

A ball is thrown straight up with an initial velocity of $$20\ \mathrm{m/s}. $$Neglecting air resistance, what is its velocity at the peak of its motion?

Accepted Answer

$$0\ \mathrm{m/s}$$

Question 6

If a velocity vs. time graph is a straight horizontal line above the time axis, what does this indicate about the object's motion?

Accepted Answer

The object is moving at a constant positive velocity.

Question 7

A helicopter rises steadily at $$2\ \mathrm{m/s}$$ while lifting a box on a $$25\ \mathrm{m}$$ rope. If the rope breaks after $$1.5\ \mathrm{s}$$, how far below the helicopter is the box at that instant? (Assume $$g = 9.8\ \mathrm{m/s^2$}$$ and neglect air resistance.)

Accepted Answer

$$13.5\ \mathrm{m}$$

Question 8

Which of the following best describes 'freefall' in physics?

Accepted Answer

Motion under the influence of gravity only, with no other forces acting.

Question 9

A position vs. time graph shows a curve that is concave upward. What does this indicate about the object's acceleration?

Accepted Answer

The object has positive acceleration.

Question 10

A runner accelerates from $$3\ \mathrm{m/s} to$$ $$9\ \mathrm{m/s} in$$ $$2\ \mathrm{s}. $$What is the runner's average acceleration?

Accepted Answer

$$3\ \mathrm{m/s^2$}$$

Question 11

Which of the following is NOT a valid SI unit for acceleration?

Accepted Answer

$$\mathrm{m/s}$$

Question 12

A rock is dropped from rest from a cliff. How far does it fall in $$3\ \mathrm{s}$$? (Assume $$g = 9.8\ \mathrm{m/s^2$}$$ and neglect air resistance.)

Accepted Answer

$$44.1\ \mathrm{m}$$

Question 13

Which kinematic variable represents the change in position over an interval?

Accepted Answer

$$\Delta x$$

Question 14

If an object has a negative velocity and a negative acceleration, what is happening to its speed?

Accepted Answer

It is speeding up.

Question 15

A cyclist travels $$100\ \mathrm{m}$$ north in $$20\ \mathrm{s}$$, then $$100\ \mathrm{m}$$ south in $$20\ \mathrm{s}. $$What is the average velocity for the entire trip?

Accepted Answer

$$0\ \mathrm{m/s}$$

Question 16

Which of the following is true about the relationship between position and velocity graphs?

Accepted Answer

The slope of the position vs. time graph gives the velocity.

Question 17

A car moves with a constant acceleration of $$-3\ \mathrm{m/s^2$}$$, starting from $$15\ \mathrm{m/s}. $$How long does it take to come to rest?

Accepted Answer

$$5\ \mathrm{s}$$

Question 18

Which equation would you use to find the final velocity of an object given its initial velocity, acceleration, and displacement?

Accepted Answer

$$v_f^2$ = v_i^2$ + 2a\Delta x$$

Question 19

A student claims that the area under a velocity vs. time graph represents the object's acceleration. Is this correct?

Accepted Answer

No, the area under a velocity vs. time graph represents displacement.

Question 20

A ball is thrown downward with an initial velocity of $$5\ \mathrm{m/s}$$ from a height of $$20\ \mathrm{m}. $$How long does it take to hit the ground? (Use $$g = 9.8\ \mathrm{m/s^2$}$$ and solve the quadratic equation.)

Accepted Answer

About $$1.23\ \mathrm{s}$$

Kinematics and Particle Models: Study Notes for Introductory Physics

Guida di studio - Domande di pratica

Study guide - Flashcard