Q: Which equation correctly expresses the work done by a constant force $$\vec{F}$$ acting over a displacement $$\vec{d}$$?

$$W = F \cdot d \cdot \cos\theta$$

Q: A projectile is launched at an angle $$\theta$$ with initial speed $$v_0. $$Which formula gives the maximum height reached?

$$h_{max} = \dfrac{v_0$^2 \sin^2$\theta}{2g}$$

Question 1

A ball is thrown horizontally from the top of a 45 m high cliff with an initial speed of 10 m/s. Neglecting air resistance, how far from the base of the cliff will the ball land? (Use $$g = 9.8\ \mathrm{m/s^2$})$$

Accepted Answer

$$30.3\ \mathrm{m}$$

Question 2

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

Accepted Answer

An object at rest remains at rest, and an object in motion remains in motion at constant velocity unless acted upon by a net external force.

Question 3

A car of mass $$1200\ \mathrm{kg}$$ traveling at $$25\ \mathrm{m/s}$$ collides with a stationary truck of mass $$1800\ \mathrm{kg}. If $$the two vehicles stick together after the collision, what is their final velocity?

Accepted Answer

$$10.7\ \mathrm{m/s}$$

Question 4

Which equation correctly expresses the work done by a constant force $$\vec{F}$$ acting over a displacement $$\vec{d}$$?

Accepted Answer

$$W = F \cdot d \cdot \cos	heta$$

Question 5

A 2 kg block slides down a frictionless incline of height 5 m. What is its speed at the bottom?

Accepted Answer

$$9.9\ \mathrm{m/s}$$

Question 6

Which of the following is a scalar quantity?

Accepted Answer

Speed

Question 7

A projectile is launched at an angle $$	heta$$ with initial speed $$v_0. $$Which formula gives the maximum height reached?

Accepted Answer

$$h_{max} = \dfrac{v_0$^2 \sin^2$	heta}{2g}$$

Question 8

A student pushes a box across a rough floor at constant speed. Which statement is true about the forces acting on the box?

Accepted Answer

The applied force is equal to the friction force.

Question 9

Which of the following best describes the principle of conservation of momentum?

Accepted Answer

The total momentum of a closed system remains constant if no external forces act on it.

Question 10

A disk rotates with constant angular acceleration $$\alpha. If $$its initial angular velocity is $$\$$omega_0$$, what is its angular velocity after time t$?

Accepted Answer

$$\omega = \$$omega_0$$ + \alpha t$$

Question 11

A 0.5 kg ball is attached to a string and swung in a horizontal circle of radius 2 m at a speed of 4 m/s. What is the tension in the string?

Accepted Answer

$$4\ \mathrm{N}$$

Question 12

Which of the following is NOT a valid application of Newton's Third Law?

Accepted Answer

A single object exerts a force on itself to move.

Question 13

A block of mass $$m$$ slides on a frictionless surface and collides elastically with a stationary block of mass $$2m. $$What is the velocity of the first block after the collision?

Accepted Answer

$$0$$

Question 14

Which formula gives the centripetal acceleration $$a_c of an $$object moving in a circle of radius $$r at $$speed $$v$$?

Accepted Answer

$$a_c = \dfrac{v^2$}{r}$$

Question 15

A 3 kg object is dropped from rest from a height of 10 m. What is its velocity just before hitting the ground? (Neglect air resistance)

Accepted Answer

$$14.0\ \mathrm{m/s}$$

Question 16

Which of the following statements about energy is correct?

Accepted Answer

Potential energy can be negative depending on the reference point.

Question 17

A force of $$5\ \mathrm{N} is $$applied to a $$2\ \mathrm{kg}$$ object for $$3\ \mathrm{s}. $$What is the change in velocity of the object?

Accepted Answer

$$3.0\ \mathrm{m/s}$$

Question 18

Which of the following is the correct expression for torque $$	au$$ produced by a force $$F at a $$distance $$r$$ from the axis, at angle $$	heta$$?

Accepted Answer

$$	au = F r \sin	heta$$

Question 19

A uniform beam of length 4 m and mass 20 kg is supported at its center. A 10 kg mass is hung 1 m from one end. What is the force required at the opposite end to keep the beam in equilibrium?

Accepted Answer

$$49\ \mathrm{N}$$

PHY 220 General Physics I – Syllabus and Study Guide

Guida di studio - Domande di pratica

Study guide - Flashcard