Q: A ball is thrown vertically upward with an initial velocity of $$20 m/s. $$Neglecting air resistance, how long does it take for the ball to return to the thrower's hand?

$$4.08 s$\ (t = \frac{2v_0}{g} = \frac{2 \times 20}{9.8})$$

Question 1

A car moves along a straight road such that its position as a function of time is given by $$x(t) = 4t^2$ + 2t + 1 ($$where $$x is in $$meters and $$t in $$seconds). What is the car's instantaneous velocity at $$t = 3 s$$?

Accepted Answer

$$v = 26 m/s$$

Question 2

A ball is thrown vertically upward with an initial velocity of $$20 m/s. $$Neglecting air resistance, how long does it take for the ball to return to the thrower's hand?

Accepted Answer

$$4.08 s$\ (t = \frac{2v_0}{g} = \frac{2 	imes 20}{9.8})$$

Question 3

Which of the following statements about free fall is correct?

Accepted Answer

All objects in free fall, regardless of mass, have the same acceleration if air resistance is negligible.

Question 4

A train travels 30 km in 20 minutes at a constant speed. How far will it travel in 1 hour at the same speed?

Accepted Answer

90 km

Question 5

The area under a velocity-versus-time graph between $$t = 0 s $$and $$t = 5 s $$represents:

Accepted Answer

The object's displacement during that time interval.

Question 6

A car accelerates from rest at $$3 m/s$^2$$ for $$4$$ seconds. What is its final velocity?

Accepted Answer

$$v = 12 m/s$$

Question 7

A cyclist riding at $$10 m/s $$sees a stop sign and comes to a complete stop in $$5 s. $$What is the magnitude of the cyclist's acceleration?

Accepted Answer

$$0.5 m/s$^2$$

Question 8

A position-versus-time graph is a straight line with a negative slope. What does this indicate about the object's motion?

Accepted Answer

The object is moving with constant negative velocity.

Question 9

A rock is dropped from rest from a cliff and hits the ground after $$2 s. $$What is the height of the cliff? (Use $$g = 9.8 m/s$^2)$$

Accepted Answer

$$h = 39.2 m$

Question 10

A car moves with a velocity given by $$v(t) = 6t (in m/s). $$What is the car's acceleration?

Accepted Answer

$$a = 6 m/s$^2$$

Question 11

A Boeing 747 accelerates at $$2.6 m/s$^2$$ and needs to reach a takeoff speed of $$70 m/s. $$What is the minimum runway length required for takeoff, assuming it starts from rest?

Accepted Answer

$$x = 940 m$$

Question 12

Which of the following best describes the acceleration of a ball at the very top of its trajectory when thrown straight up?

Accepted Answer

The acceleration is $$-g ($$downward).

Question 13

A drag racer starts from rest and travels $$6.0 m in$$ $$1.0 s. If $$the acceleration remains constant, how far will the car travel in $$5.0 s$$?

Accepted Answer

$$150 m$$

Question 14

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

Accepted Answer

The object could be at rest or changing direction.

Question 15

A student walks $$200 m in$$ $$4$$ min, then $$300 m in$$ $$6$$ min. What is the student's average speed for the entire trip?

Accepted Answer

$$50 m/$$min

Question 16

A velocity-versus-time graph is a horizontal line above the time axis. What does this indicate about the object's motion?

Accepted Answer

The object moves with constant positive velocity.

Question 17

A car slows down while moving in the positive x-direction. What is the sign of its acceleration?

Accepted Answer

Negative

Question 18

A ball is dropped from a height $$h$$ and takes time $$t to $$reach the ground. If the height is quadrupled, how long does it take to reach the ground?

Accepted Answer

$$2t$$

Question 19

Which of the following is an example of uniform motion?

Accepted Answer

A hockey puck sliding in a straight line at a constant speed.

Question 20

A car starts from rest and accelerates uniformly at $$2 m/s$^2$$ for $$10 s. $$What is the total distance traveled?

Accepted Answer

$$100 m$$

Chapter 2: Motion in One Dimension – Physics with Calculus Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard