Physics 11 H. - Term II Exam Questions

Physics 11 H. - Term II Exam questions

1- An object is thrown with an initial velocity of 14.4m/s 30.0° higher than horizontal from the top of a hill. The hill has a slope of 23.0°. How long is the object airborne? = 2.55s

2- An object is given an initial velocity of 12.0m/s @ 39.0° above horizontal. What is its total displacement after 1.42s? = 13.3m [3.64° above horizontal 3- A 5 kg block is pulled across a table by a horizontal force of 40 N with a frictional force of 8 N opposing the motion. Calculate the acceleration of the object? Answer= 6.4m/s^2

4- A satellite has a mass of 3.25 × 103 kg while a polar bear on Earth has a mass of 3.70 × 105 grams. If the distance between the satellite and the polar bear is 8.0 × 104 km and the gravitational constant is 6.67 × 10-11 N (m/kg) 2, what is the gravitational force between them? Answer: 1.3 × 10 -20 N 5- A rocket is launched horizontally from a 44m high cliff at 15 m/s. How long will the rocket take to reach the bottom of the cliff, and how far away from the cliff is it?

t = square root(2d/g) = square root(2(44)/9.8) ~ 3.0 s dx = vxt = (15m/s)(3.0s) = 45 m ~ 4.5x10^1

6- A box of mass 4.0kg rests on an inclined plane which is at an angle of 15 degree with respect to the horizontal. A string is tied to the box, and it exerts a force of 5.0N up the ramp. What is the acceleration (magnitude and direction)?

Answer: Fnet=Ft-Fg(sin15) ma=5.0N-4.0kg•9.8m/s2•sin15 ma=-5.1456=-5.1N a=-5.1456N/4.0kg=-1.286=-1.3m/s2=1.3m/s2[down]

7- You are rowing a boat across a river, trying to get to the other side of the river. You are rowing 5 km/h and the water is flowing down at 3 km/h. If the river is 100 wide, a) how long will it take the boat to cross the river Ans: 72 seconds b) how far down river will you land on the other side Ans: 0.06km

8- A sign that weighs 200 N is supported by 2 ropes that make 25 degress angle with the horizontal sign is not moving. What forces do the rope exert on the sign? Ans: 240 N