Q: A car moving at $$15 \\text{ m/s}$$ sees a tree $$50 \\text{ m}$$ ahead and decelerates at $$-3 \\text{ m/s}^2. $$Will the car stop before hitting the tree?

Yes, because the stopping distance is $$37.5 \\text{ m}.$$

Question 1

Which of the following best describes displacement?

Accepted Answer

The change in position of an object, measured as a straight line from initial to final position.

Question 2

A car travels at 15 m/s and suddenly applies brakes, decelerating at $$-3 \text{ m/s}^2. $$How long does it take to come to a complete stop?

Accepted Answer

$$5 \text{ s}$$

Question 3

Convert 14 days to seconds.

Accepted Answer

$$1,209,600 \text{ s}$$

Question 4

A ball is thrown upwards with a velocity of $$45 \text{ m/s}$$ and returns to its starting point. Ignoring air resistance, what is its speed as it passes the initial location on the way down?

Accepted Answer

$$45 \text{ m/s}$$

Question 5

A force has $$x$$ and $$y$$ components of $$30 \text{ N}$$ and $$40 \text{ N}$$ respectively. What is the magnitude of the resultant force?

Accepted Answer

$$50 \text{ N}$$

Question 6

A 10 kg mass is acted upon by a resultant force of $$50 \text{ N}. $$What is the acceleration produced?

Accepted Answer

$$5 \text{ m/s}^2$$

Question 7

A ball is kicked at $$16.0 \text{ m/s} at an $$angle of $$65^\circ$$ above the horizontal. What is the initial vertical component of velocity?

Accepted Answer

$$14.5 \text{ m/s}$$

Question 8

A ball is thrown horizontally at $$8 \text{ m/s}$$ from a $$10 \text{ m}$$ high rooftop. How long does it take to hit the ground?

Accepted Answer

$$1.43 \text{ s}$$

Question 9

A car moving at $$80 \text{ m/s}$$ comes to a stop after traveling $$400 \text{ m}. $$What is the magnitude of its acceleration, assuming it is constant?

Accepted Answer

$$-8 \text{ m/s}^2$$

Question 10

A person weighs $$700 \text{ N} on $$Earth. What is his mass?

Accepted Answer

$$71.4 \text{ kg}$$

Question 11

If you drop an object from a height of $$20 \text{ m} on $$Earth $$(g = 9.8 \text{ m/s}^2)$$ and Mars $$(g = 3.2 \text{ m/s}^2)$$, which statement is correct?

Accepted Answer

The object takes longer to fall on Mars than on Earth.

Question 12

A car moving at $$15 \text{ m/s}$$ sees a tree $$50 \text{ m}$$ ahead and decelerates at $$-3 \text{ m/s}^2. $$Will the car stop before hitting the tree?

Accepted Answer

Yes, because the stopping distance is $$37.5 \text{ m}.$$

Question 13

What is the formula for weight?

Accepted Answer

$$W = mg$$

Question 14

A ball is kicked at $$16.0 \text{ m/s} at$$ $$65^\circ$$ above the horizontal. How long is it in the air? (Assume $$g = 9.8 \text{ m/s}^2)$$

Accepted Answer

$$2.96 \text{ s}$$

Question 15

Which of the following is a vector quantity?

Accepted Answer

Velocity

Question 16

A $$800 \text{ g}$$ object has a mass of how many kilograms?

Accepted Answer

$$0.8 \text{ kg}$$

Question 17

A ball is thrown horizontally at $$8 \text{ m/s}$$ from a $$10 \text{ m}$$ high rooftop. What is its horizontal range?

Accepted Answer

$$11.44 \text{ m}$$

Question 18

A car moving at $$15 \text{ m/s}$$ delays braking for $$2 \text{ s}$$ before decelerating at $$-3 \text{ m/s}^2. If $$the tree is $$50 \text{ m}$$ away, what speed will the car hit the tree?

Accepted Answer

$$9.49 \text{ m/s}$$

Question 19

Which equation represents Newton's Second Law?

Accepted Answer

$$F = ma$$

Fundamental Concepts and Practice Problems in Introductory Physics (Kinematics & Dynamics)

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드