Question 1

A person is walking down the aisle of a moving train, as shown in the first image. If the train moves east at $$20\ \mathrm{m/s}$$ and the person walks west at $$2\ \mathrm{m/s}$$ relative to the train, what is the person's velocity relative to the ground?

Accepted Answer

$$18\ \mathrm{m/s}$$\ east

Question 2

Refer to the second image. A person walks $$40\ \mathrm{m}$$ east, then $$30\ \mathrm{m}$$ west. What is the displacement and the total distance traveled?

Accepted Answer

Displacement: $$10\ \mathrm{m}$$ east; Distance: $$70\ \mathrm{m}$$

Question 3

A runner moves from $$x_1 = 10$$\ \mathrm{m}$$ to x_2$ = 30\ \mathrm{m} in$$ $$4\ \mathrm{s}. $$What is the average velocity?

Accepted Answer

$$5\ \mathrm{m/s}$$

Question 4

A runner starts at $$x_1 = 30$$\ \mathrm{m}$$ and ends at x_2$ = 10\ \mathrm{m} in$$ $$4\ \mathrm{s}. $$What is the average velocity?

Accepted Answer

$$-5\ \mathrm{m/s}$$

Question 5

A runner starts at $$x_1 = 50.0$$\ \mathrm{m}$$ and finishes at x_2$ = 30.5\ \mathrm{m} in$$ $$3.00\ \mathrm{s}. $$What is the average velocity?

Accepted Answer

$$-6.5\ \mathrm{m/s}$$

Question 6

Given $$x(t) = 5t^2$ + 3t - 1$$, what is the instantaneous velocity at $$t = 2\ \mathrm{s}$$?

Accepted Answer

$$v = 23\ \mathrm{m/s}$$

Question 7

Which of the following statements is true about instantaneous speed and velocity?

Accepted Answer

Instantaneous speed always equals the magnitude of instantaneous velocity.

Question 8

A car's velocity changes from $$v_1 = -15.0$$\ \mathrm{m/s}$$ to v_2$ = -5.0\ \mathrm{m/s} in$$ $$2.0\ \mathrm{s}. $$What is the average acceleration?

Accepted Answer

$$5.0\ \mathrm{m/s^2$}$$

Question 9

A car accelerates from rest at $$2.00\ \mathrm{m/s^2$}$$ across a $$30.0\ \mathrm{m}$$ intersection. How long does it take to cross?

Accepted Answer

$$5.48\ \mathrm{s}$$

Question 10

A ball is thrown downward from a tower with an initial velocity of $$3.00\ \mathrm{m/s}. $$What is its position after $$2.00\ \mathrm{s}$$? (Take $$g = 9.80\ \mathrm{m/s^2$}$$, downward is positive, initial position is $$0.)$$

Accepted Answer

$$25.6\ \mathrm{m}$$

Question 11

A ball is thrown upward with an initial velocity of $$15.0\ \mathrm{m/s}. $$How high does it go? (Ignore air resistance, $$g = 9.80\ \mathrm{m/s^2$})$$

Accepted Answer

$$11.5\ \mathrm{m}$$

Question 12

Which of the following is NOT a correct equation for motion with constant acceleration?

Accepted Answer

$$x = x_0$ + v t + \frac{1}{2} a t^2$

Question 13

If the velocity of an object is zero at some instant, which of the following must be true?

Accepted Answer

The acceleration could be nonzero.

Question 14

A ball is dropped from rest. How far does it fall in $$2.0\ \mathrm{s}$$? (Ignore air resistance, $$g = 9.80\ \mathrm{m/s^2$})$$

Accepted Answer

$$19.6\ \mathrm{m}$$

Question 15

Which of the following best describes the difference between distance and displacement?

Accepted Answer

Distance is a scalar; displacement is a vector.

Question 16

A car moves with a constant velocity of $$40\ \mathrm{km/h}$$ for $$0.5\ \mathrm{h}. $$What is the total displacement?

Accepted Answer

$$20\ \mathrm{km}$$

Question 17

A car accelerates from $$0 to$$ $$100\ \mathrm{km/h} in$$ $$10.0\ \mathrm{s}. $$What is the average acceleration in $$\mathrm{m/s^2$}$$?

Accepted Answer

$$2.78\ \mathrm{m/s^2$}$$

Kinematics in One Dimension: Structured Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard