Q: A rectangular field has a length of $$95.7\ \mathrm{m}$$ and a width of $$108.6\ \mathrm{m}. $$What is the area of the field, reported to the correct number of significant figures?

$$1.04 \times 10^4$\ \mathrm{m}^2$$

Q: The mass of a bacterium is about $$1.23 \times 10$$^{-13}$$\ \mathrm{kg}. If a $$petri dish contains $$2.75 \times 10^9$ bacteria, what is the combined mass of all the bacteria?

$$3.38 \times 10$$^{-4}$$\ \mathrm{kg}$$

Q: A plot of land contains $$5.8$$ acres. How many square meters does it contain? ($$1.0\ \mathrm{acre} = 43,560\ \mathrm{ft}^2$$, $$2.54\ \mathrm{cm} = 1.00\ \mathrm{in})$$

$$2.3 \times 10^4$\ \mathrm{m}^2$$

Q: An oak tree was planted $$22.00$$ years ago. How many seconds is this? (Assume a year is exactly $$365$$ days.)

$$6.938 \times 10^8$\ \mathrm{s}$$

Question 1

Evaluate the expression $$3.125 	imes 0.03974 + 21.1$$ and report your answer to the correct number of significant figures.

Accepted Answer

$$0.124 + 21.1 = 21.2$$

Question 2

Why is the metric system preferred over the British (Imperial) system in scientific work?

Accepted Answer

Conversions between metric quantities are especially easy because they are all related by factors of ten.

Question 3

A reasonable estimate for the mass of a typical male college student is:

Accepted Answer

85 kg

Question 4

A rectangular field has a length of $$95.7\ \mathrm{m}$$ and a width of $$108.6\ \mathrm{m}. $$What is the area of the field, reported to the correct number of significant figures?

Accepted Answer

$$1.04 	imes 10^4$\ \mathrm{m}^2$$

Question 5

The mass of a bacterium is about $$1.23 	imes 10$$^{-13}$$\ \mathrm{kg}. If a $$petri dish contains $$2.75 	imes 10^9$ bacteria, what is the combined mass of all the bacteria?

Accepted Answer

$$3.38 	imes 10$$^{-4}$$\ \mathrm{kg}$$

Question 6

A volume of $$100\ \mathrm{mL} is $$equivalent to which one of the following volumes?

Accepted Answer

$$0.1\ \mathrm{L}$$

Question 7

Express $$50$$ miles per hour in units of meters per second. ($$1\ \mathrm{mi} = 1609\ \mathrm{m})$$

Accepted Answer

$$22.3\ \mathrm{m/s}$$

Question 8

A plot of land contains $$5.8$$ acres. How many square meters does it contain? ($$1.0\ \mathrm{acre} = 43,560\ \mathrm{ft}^2$$, $$2.54\ \mathrm{cm} = 1.00\ \mathrm{in})$$

Accepted Answer

$$2.3 	imes 10^4$\ \mathrm{m}^2$$

Question 9

An oak tree was planted $$22.00$$ years ago. How many seconds is this? (Assume a year is exactly $$365$$ days.)

Accepted Answer

$$6.938 	imes 10^8$\ \mathrm{s}$$

Question 10

True or False: The magnitude of the sum of two vectors can not be less than either of the two vectors.

Accepted Answer

False

Question 11

True or False: The magnitude of a vector can never be less than the magnitude of any of its components.

Accepted Answer

True

Question 12

A bird flies $$35$$ miles due east, then $$20$$ miles at $$15^{\circ}$$ north of west. What is the bird’s final displacement vector (magnitude and direction relative to east)?

Accepted Answer

$$16.5$$ miles at $$18.3^{\circ}$$ north of east

Question 13

A rock is dropped from a $$250\ \mathrm{m}$$ tall cliff. How long does it take to hit the bottom? (Assume $$g = 9.8\ \mathrm{m/s}^2$$ and no air resistance.)

Accepted Answer

$$7.14\ \mathrm{s}$$

Question 14

A rock is thrown directly downward from a $$250\ \mathrm{m}$$ tall cliff at an initial velocity of $$20\ \mathrm{m/s}. $$How long does it take to hit the bottom? (Assume $$g = 9.8\ \mathrm{m/s}^2$$ and no air resistance.)

Accepted Answer

$$5.39\ \mathrm{s}$$

Question 15

A rock is thrown at an angle of $$10^{\circ}$$ above the horizontal from a $$250\ \mathrm{m}$$ tall cliff at an initial velocity of $$15\ \mathrm{m/s}. $$How long until it hits the bottom? (Assume $$g = 9.8\ \mathrm{m/s}^2$$ and no air resistance.)

Accepted Answer

$$7.41\ \mathrm{s}$$

Question 16

An astronaut on the moon (where $$g = 1.62\ \mathrm{m/s}^2) $$drops a rock into a crater and measures $$12.2\ \mathrm{s}$$ for it to hit the bottom. How deep is the crater?

Accepted Answer

$$121\ \mathrm{m}$$

Question 17

A puma jumps straight up with a launch velocity of $$10\ \mathrm{m/s}. $$How high does it rise at the top of its leap? (Assume $$g = 9.8\ \mathrm{m/s}^2.)$$

Accepted Answer

$$5.1\ \mathrm{m}$$

Question 18

Which of the following best explains why the metric system is easier for scientific calculations than the British system?

Accepted Answer

Metric units are based on powers of ten, making conversions straightforward.

Question 19

A scientist needs to convert $$100\ \mathrm{mL} to $$liters for a chemical solution. What is the correct conversion?

Accepted Answer

$$0.1\ \mathrm{L}$$

Physics 2010 Practice Exam 1 – Step-by-Step Study Guidance

Guida di studio - Domande di pratica

Study guide - Flashcard