Q: A weight lifter can bench press $$171\ \mathrm{kg}. $$How many milligrams (mg) is this?

$$1.71 \times 10^8$\ \mathrm{mg}$$

Q: A person on a diet loses $$1.6\ \mathrm{kg} in a $$week. How many micrograms per second ($$\mu\mathrm{g/s}) $$are lost?

$$2.6 \times 10^3$\ \mu\mathrm{g/s}$$

Question 1

Express $$1.2 	imes 10$$^{-3}$$ in decimal notation.

Accepted Answer

$$0.0012$$

Question 2

How many significant figures does the number $$0.003010$$ have?

Accepted Answer

4 significant figures

Question 3

The length and width of a rectangle are $$1.125\ \mathrm{m}$$ and $$0.606\ \mathrm{m}$$, respectively. Multiplying, your calculator gives the product as $$0.68175. $$Rounding properly to the correct number of significant figures, the area should be written as:

Accepted Answer

$$0.682\ \mathrm{m}^2$$

Question 4

A weight lifter can bench press $$171\ \mathrm{kg}. $$How many milligrams (mg) is this?

Accepted Answer

$$1.71 	imes 10^8$\ \mathrm{mg}$$

Question 5

A supercomputer can perform $$6.7 	imes 10^7$ calculations per second. How many calculations does it perform in 15$$\ \mathrm{ms}$$?

Accepted Answer

$$1.0 	imes 10^6$

Question 6

A person on a diet loses $$1.6\ \mathrm{kg} in a $$week. How many micrograms per second ($$\mu\mathrm{g/s}) $$are lost?

Accepted Answer

$$2.6 	imes 10^3$\ \mu\mathrm{g/s}$$

Question 7

Convert a speed of $$4.50\ \mathrm{km/h} to $$units of $$\mathrm{ft/min}$$. ($$1.00\ \mathrm{m} = 3.28\ \mathrm{ft})$$

Accepted Answer

$$246\ \mathrm{ft/min}$$

Question 8

The slope at a point on a position-versus-time graph of an object is:

Accepted Answer

The object's velocity at that point.

Question 9

Suppose we define the y-axis to point vertically upward. When an object is in free fall, it has acceleration in the y-direction:

Accepted Answer

$$a_y = g$$, where $$g = -9.80\ \mathrm{m/s}^2$$

Question 10

Which of the following statements about acceleration due to gravity is correct?

Accepted Answer

It is always directed toward the center of the Earth.

Question 11

A car travels $$55\ \mathrm{m}$$ north, then $$55\ \mathrm{m}$$ east. What is the magnitude of the displacement?

Accepted Answer

$$77.8\ \mathrm{m}$$

Question 12

Given vectors $$\vec{A} = 100\hat{i} + 200\hat{j}$$ and $$\vec{B} = 200\hat{i} + 800\hat{j}$$, what is the magnitude and direction of $$\vec{C} = \vec{A} + \vec{B}$$?

Accepted Answer

Magnitude: $$\sqrt{(300)^2$ + (1000)^2$} = 1044\ \mathrm{units}$$, Direction: $$73.3^\circ$$ above x-axis

Question 13

Which of the following is a vector quantity?

Accepted Answer

Displacement

Question 14

A ball is thrown vertically upward with an initial velocity of $$20\ \mathrm{m/s}. $$What is its velocity after $$2.0\ \mathrm{s}$$? (Take $$g = 9.8\ \mathrm{m/s}^2$$ downward.)

Accepted Answer

$$0.4\ \mathrm{m/s}$$

Question 15

Which of the following best describes the acceleration of an object in free fall (neglecting air resistance)?

Accepted Answer

It is constant and directed downward.

Question 16

A runner covers $$100\ \mathrm{m} in$$ $$10\ \mathrm{s}. $$What is the average speed?

Accepted Answer

$$10\ \mathrm{m/s}$$

Question 17

Which of the following statements about significant figures is correct?

Accepted Answer

Zeros between nonzero digits are always significant.

Question 18

Which of the following is NOT a scalar quantity?

Accepted Answer

Velocity

Physics Fundamentals: Units, Significant Figures, Vectors, and Kinematics

Guida di studio - Domande di pratica

Study guide - Flashcard