Question 1

A ball is thrown upward with a speed of $$v_0. If it $$reaches a maximum height of $$12.6\ \mathrm{m}$$ above the initial point, what is $$v_0$$? (Assume $$g = 9.8\ \mathrm{m/s^2$})$$

Accepted Answer

$$v_0 = 15.7$$\ \mathrm{m/s}$$

Question 2

A ball is thrown horizontally at $$50.0\ \mathrm{m/s}$$ from a $$26.7\ \mathrm{m}$$ high cliff. How far from the cliff does the ball land? (Neglect air resistance)

Accepted Answer

$$22.9\ \mathrm{m}$$

Question 3

Tony Stark has a lovely crystal hummingbird feeder he wishes to give to Pepper Potts. He is holding it by a string which will break if the tension exceeds $$300\ \mathrm{N}. $$The mass of the feeder is $$16.8\ \mathrm{kg}. He $$puts on Ironman suit and flies upward. What is the greatest acceleration he can use?

Accepted Answer

$$a = 27.1\ \mathrm{m/s^2$}$$

Question 4

A ramp is tilted at $$27^{\circ}$$ with respect to the horizontal. A box of mass $$10\ \mathrm{kg}$$ sits on the ramp without moving. What is the component of the weight of the box that is directed perpendicular to the ramp?

Accepted Answer

$$87.3\ \mathrm{N}$$

Question 5

A $$2.73\ \mathrm{kg}$$ box slides across a horizontal floor. It begins with a speed of $$9.8\ \mathrm{m/s}$$ and comes to rest after sliding $$17.6\ \mathrm{m}. $$What is the coefficient of kinetic friction between the box and the floor?

Accepted Answer

$$\mu_k = 0.28$$

Question 6

Flash the ant sees a tasty corn flake $$0.45\ \mathrm{m}$$ away. She puts on the Flash suit and zooms toward the corn flake at her fastest speed. Grabbing the flake in zero time, she is a bit slower getting back because corn flakes are heavy. She travels back at only $$1/3 of $$the speed she made going out to the flake. The total time for the trip was $$3.60\ \mathrm{s}. $$What is her fastest speed?

Accepted Answer

$$0.375\ \mathrm{m/s}$$

Question 7

Jane and John have new rocket bikes and want to race. Jane's bike accelerates at $$14.1\ \mathrm{m/s^2$}$$ but John's has a fuel filter issue and only accelerates at $$13.9\ \mathrm{m/s^2$}. $$They decide to give John a $$1.45\ \mathrm{m/s}$$ head start. How far from the starting line will they be when Jane flashes past John? How much faster than John will Jane be going when she passes him?

Accepted Answer

Distance $$= 1.47\ \mathrm{km}$$, Speed difference $$= 4.2\ \mathrm{m/s}$$

Question 8

Find the acceleration of the blocks in the figure below. The pulley is ideal (no mass, no friction). There is friction on the inclines. The coefficient of friction is $$\mu = 0.1. $$Masses: $$m_1 = 30$$\ \mathrm{kg}$$, m_2$ = 40\ \mathrm{kg}.$$

Accepted Answer

$$a = 1.29\ \mathrm{m/s^2$}$$

Question 9

A $$5.0\ \mathrm{kg}$$ object is dropped from a height of $$20.0\ \mathrm{m}. $$What is its speed just before hitting the ground? (Neglect air resistance)

Accepted Answer

$$v = 19.8\ \mathrm{m/s}$$

Question 10

A $$10\ \mathrm{kg}$$ box is pulled across a rough floor with a force of $$50\ \mathrm{N} at an $$angle of $$30^{\circ}$$ above the horizontal. The coefficient of kinetic friction is $$0.2. $$What is the acceleration of the box?

Accepted Answer

$$a = 2.1\ \mathrm{m/s^2$}$$

Question 11

A car traveling at $$25\ \mathrm{m/s}$$ comes to a stop in $$4.0\ \mathrm{s}$$ due to constant braking force. What is the magnitude of the acceleration?

Accepted Answer

$$a = 6.25\ \mathrm{m/s^2$}$$

Question 12

A $$2.0\ \mathrm{kg}$$ block slides down a $$30^{\circ}$$ incline that is $$5.0\ \mathrm{m}$$ long. The coefficient of kinetic friction is $$0.15. $$What is the speed of the block at the bottom?

Accepted Answer

$$v = 5.2\ \mathrm{m/s}$$

Question 13

A $$0.5\ \mathrm{kg}$$ ball is attached to a $$1.2\ \mathrm{m}$$ string and swung in a horizontal circle at $$2.0\ \mathrm{m/s}. $$What is the tension in the string?

Accepted Answer

$$T = 1.7\ \mathrm{N}$$

Question 14

A $$3.0\ \mathrm{kg}$$ object moves in a circle of radius $$0.5\ \mathrm{m} at a $$constant speed of $$4.0\ \mathrm{m/s}. $$What is the centripetal force acting on the object?

Accepted Answer

$$F_c = 96\ \mathrm{N}$$

Question 15

A $$1.5\ \mathrm{kg}$$ block is attached to a spring with spring constant $$k = 200\ \mathrm{N/m}. If $$the block is pulled $$0.10\ \mathrm{m}$$ from equilibrium and released, what is its maximum speed?

Accepted Answer

$$v_{max} = 1.15\ \mathrm{m/s}$$

Question 16

A $$0.2\ \mathrm{kg}$$ ball is dropped from a height of $$10\ \mathrm{m}. $$What is its kinetic energy just before it hits the ground?

Accepted Answer

$$KE = 19.6\ \mathrm{J}$$

Question 17

A $$5.0\ \mathrm{kg}$$ object is moving at $$3.0\ \mathrm{m/s}. $$What is its momentum?

Accepted Answer

$$p = 15.0\ \mathrm{kg\cdot m/s}$$

Question 18

A $$2.0\ \mathrm{kg}$$ block moving at $$5.0\ \mathrm{m/s}$$ collides with a stationary $$3.0\ \mathrm{kg}$$ block. If the collision is perfectly inelastic, what is their final velocity?

Accepted Answer

$$v_f = 2.0\ \mathrm{m/s}$$

Exam one Study Notes from practice exam

Guida di studio - Domande di pratica

Study guide - Flashcard