Q: A $$2\ \mathrm{kg}$$ object is dropped from a height of $$10\ \mathrm{m}. $$Ignoring air resistance, what is its velocity just before hitting the ground? (Use $$g = 9.8\ \mathrm{m/s^2$})$$

$$v = \sqrt{2gh} = \sqrt{2 \times 9.8 \times 10} = 14\ \mathrm{m/s}$$

Q: A wire carries a current of $$2\ \mathrm{A}$$ and is placed perpendicular to a magnetic field of $$0.5\ \mathrm{T}. If $$the length of the wire in the field is $$0.3\ \mathrm{m}$$, what is the magnitude of the force on the wire?

$$F = 0.5 \times 2 \times 0.3 = 0.3\ \mathrm{N}$$

Question 1

A car travels in a straight line with a constant velocity of $$20\ \mathrm{m/s}$$ for $$10\ \mathrm{s}$$, then accelerates uniformly to $$40\ \mathrm{m/s}$$ over the next $$5\ \mathrm{s}. $$What is the total distance traveled by the car in $$15\ \mathrm{s}$$?

Accepted Answer

$$350\ \mathrm{m} + 150\ \mathrm{m} = 500\ \mathrm{m}$$

Question 2

Which of the following best describes Newton's Third Law of Motion?

Accepted Answer

For every action, there is an equal and opposite reaction.

Question 3

A $$2\ \mathrm{kg}$$ object is dropped from a height of $$10\ \mathrm{m}. $$Ignoring air resistance, what is its velocity just before hitting the ground? (Use $$g = 9.8\ \mathrm{m/s^2$})$$

Accepted Answer

$$v = \sqrt{2gh} = \sqrt{2 	imes 9.8 	imes 10} = 14\ \mathrm{m/s}$$

Question 4

A $$0.5\ \mathrm{kg}$$ ball moving at $$4\ \mathrm{m/s}$$ collides elastically with a stationary $$0.5\ \mathrm{kg}$$ ball. What is the velocity of the first ball after the collision?

Accepted Answer

$$0\ \mathrm{m/s} ($$the first ball stops, the second moves at $$4\ \mathrm{m/s})$$

Question 5

A satellite orbits Earth in a circular path. Which force is responsible for keeping it in orbit?

Accepted Answer

Gravitational force

Question 6

A hydraulic lift uses a small piston of area $$0.01\ \mathrm{m^2$}$$ and a large piston of area $$1\ \mathrm{m^2$}. If a $$force of $$100\ \mathrm{N} is $$applied to the small piston, what is the maximum weight that can be lifted by the large piston (neglecting friction)?

Accepted Answer

$$10,000\ \mathrm{N}$$

Question 7

Which of the following statements about heat transfer is correct?

Accepted Answer

Conduction requires a medium, but radiation does not.

Question 8

A $$1\ \mathrm{kg}$$ block of ice at $$0^\circ\mathrm{C} is $$placed in $$500\ \mathrm{g} of $$water at $$80^\circ\mathrm{C}. $$What is the final temperature after thermal equilibrium is reached? (Assume no heat loss, $$L_f = 334,000\ \mathrm{J/kg}$$, $$c_{water} = 4,186\ \mathrm{J/(kg\cdot K)})$$

Accepted Answer

The final temperature is $$0^\circ\mathrm{C}$$; not all the ice melts.

Question 9

Which of the following best describes Ohm's Law?

Accepted Answer

$$V = IR$$

Question 10

A wire carries a current of $$2\ \mathrm{A}$$ and is placed perpendicular to a magnetic field of $$0.5\ \mathrm{T}. If $$the length of the wire in the field is $$0.3\ \mathrm{m}$$, what is the magnitude of the force on the wire?

Accepted Answer

$$F = 0.5 	imes 2 	imes 0.3 = 0.3\ \mathrm{N}$$

Question 11

A sound wave travels at $$340\ \mathrm{m/s} in $$air. If its frequency is $$1700\ \mathrm{Hz}$$, what is its wavelength?

Accepted Answer

$$\lambda = v/f = 340/1700 = 0.2\ \mathrm{m}$$

Question 12

Which of the following best explains why the sky appears blue during the day?

Accepted Answer

Blue light is scattered more than red light by the atmosphere.

Question 13

Which of the following is a correct statement about the periodic table?

Accepted Answer

Elements in the same group have similar chemical properties.

Question 14

A radioactive isotope has a half-life of $$3$$ days. If you start with $$80\ \mathrm{g}$$, how much remains after $$9$$ days?

Accepted Answer

$$20\ \mathrm{g}$$

Question 15

A $$60\ \mathrm{W}$$ light bulb is left on for $$5$$ hours. How much energy does it use in kilowatt-hours?

Accepted Answer

$$0.3\ \mathrm{kWh}$$

Question 16

Which of the following is a real-world example of Newton's First Law?

Accepted Answer

A passenger moves forward in a car when it suddenly stops.

Question 17

Which of the following best describes the process of electromagnetic induction?

Accepted Answer

A changing magnetic field induces an electric current.

Question 18

A diverging lens forms an image of an object. Which statement is true about the image?

Accepted Answer

The image is always virtual, upright, and smaller than the object.

Question 19

Which of the following is a correct statement about energy conservation in a closed system?

Accepted Answer

The total energy remains constant, though it may change forms.

Physics I: Core Topics and Chapter Overview (Syllabus-Based Study Guide)

Guida di studio - Domande di pratica

Study guide - Flashcard