Extra Question on Force and Motion

1.

AB

____ i. displacement of the car for the first 3.0 sa. 3.0 m/s2 [W]

____ ii. velocity of the car for the last 3.0 sb. 48 m [W]

____ iii. acceleration of the car from 3.0 s to 8.0 sc. 16 m/s [W]

____ iv. displacement of the car for the total 11.0 sd. 31 m/s [W]

____ v. velocity of the car for the first 3.0 se. 260 m [W]

f. 360 m [W]

2.The town of Vector is 42.0 km [W] of the city of Scalar. There is a highway that connects the two places. A truck leaves the town of Vector and heads for Scalar. The truck travels at a constant speed of 75.0 km/h. At exactly the same time, a bus leaves Scalar and heads for Vector. The bus travels at a constant speed of 85.0 km/h.

a) Where do the two vehicles meet on the highway that connects the two places?

b) How much time (in min) passes before they meet?

3.Freda and Maria decide to have a race. Freda knows that she is a faster runner, so she gives Maria a 30.0 s head start. Maria's average velocity is 4.00 m/s [E]. Freda's average velocity is 5.00 m/s [E]. The finish line is 800 m away from the starting point.

a) How long does Freda take to run the race?

b) How long does Maria take to run the race?

c) How long does Freda take to catch up with Maria?

d) When Freda catches up with Maria, how far away are they from the starting point?

4.A soccer ball is rolling down a soccer field when a player kicks it. The ball accelerates at 0.83 m/s2 [S] for 2.8 s. After the 2.8 s, the velocity of the ball is 3.5 m/s. Calculate the displacement of the ball.

5.A race car accelerates at 4.0 m/s2 from a velocity of 6.0 m/s. Calculate how long the race car takes to travel a distance of 216 m.

6.Common Forces

AB

____ i. force that acts perpendicular to a contact surfacea. static friction

____ ii. gravitational force that acts near a planet's surfaceb. kinetic friction

____ iii. force that results when a soccer ball is kickedc. weight

____ iv. force that keeps snow from sliding down a roofd. normal force

____ v. force that opposes a toboggan as it slides down a hille. applied force

7.Newton's Three Laws of Motion

AB

____ i. You lose speed as you ride a bicycle uphill.a. Newton's first law

____ ii. A parachutist falls faster and faster to Earth.b. Newton's second law

____ iii. A moving car tries to stop at an icy intersection.c. Newton's third law

____ iv. A standing person stumbles forward as a bus

suddenly stops.

____ v. Earth attracts the Moon, and the Moon attracts Earth.

8.Forces and Motion

AB

____ i. A parachutist falls at her terminal velocity.a. net force = 0

____ ii. A cyclist travels at a constant speed.b. net force  0

____ iii. A car increases in speed when a stoplight turns green.

____ iv. A textbook is at rest on a desk

____ v. A water balloon is dropped from a window.

9.Fundamental Forces

AB

____ i. holds the nucleus of an atom togethera. gravity

____ ii. causes like charges to repel each other, andb. strong nuclear force

unlike charges to attract each otherc. weak nuclear force

____ iii. is involved in radioactive decayd. electromagnetic force

____ iv. causes matter to attract matter

____ v. is the strongest of the four fundamental forces

10.Draw a free-body diagram to show the forces that are acting on a skydiver at each point in the skydiver's fall.

a) immediately after jumping out of the airplane

b) at terminal velocity (falling at a constant maximum speed)

c) immediately after opening the parachute

11.A 40.0 kg anchor is released from rest underwater. The water provides a resistance of 375 N. How long does the anchor take to reach the bottom of the lake, which is 5.2 m down?

12.A 930 kg piano needs to be moved into an auditorium for a concert. An applied force moves the piano from rest to 0.800 m/s [forward] in 6.00 s.

a) Calculate the acceleration of the piano.

b) Determine the force of friction that is opposing the motion of the piano. The coefficient of friction between the two surfaces is  = 1.12

c) Find the applied force that is needed to move the piano with this acceleration.

13.Extremely difficult question for grade 11 – done in grade 12

Several children jump on a toboggan and ask for a ride. The coefficient of friction between the snow and the toboggan is 0.15. The total mass of the toboggan is 66 kg. The rope makes an angle of 35 with the horizontal. What applied force is needed to move the toboggan with an acceleration of 0.27 m/s2?

14.A skateboarder starts from rest and applies a force of 210 N [forward] for 10.0 s. The force of friction between the skateboard tires and the pavement is 180 N. The total mass of the skateboard and the skateboarder is 62.0 kg.

a) Calculate the total distance travelled while the force is applied.

b) Calculate the total distance travelled while the skateboard coasts to a stop.

15.The acceleration due to gravity on Mars is 3.72 m/s2. Calculate what an astronaut weighs on Earth if the astronaut would weigh 352 N on Mars.

16.A car brakes to stop at a traffic light. The mass of the car is 1700 kg.

a) Calculate the force of friction between the car tires and the asphalt if the asphalt is wet ( = 0.95).

b) Calculate the force of friction between the car tires and the asphalt if the asphalt is dry ( = 1.07).

c) On which surface can the car stop in a shorter distance? Explain your answer.

17.A hockey player has a mass of 105 kg. He is skating at a constant speed. He needs to exert a force of 10.3 N to maintain his constant speed.

a) Determine the coefficient of friction between the player's skates and the ice surface.

b) The player picks up a stack of pylons, which have a mass of 10.0 kg. What effect does this have on the coefficient of friction?

c) What force does the player need to exert to skate at a constant speed with the pylons?