PS 113 - Quiz 1

18 flashcards · Physics · by Nicholas Enoul

A commuter backs her car out of her garage with a constant acceleration of 1.30 m/s2. (a) How long in seconds does it take her to reach a speed of 1.70 m/s? (b)If she then brakes to a stop in 0.8s, what is her (constant) deceleration in m/s2
(a) 1.31 (b) 2.13
A commuter backs her car out of her garage with a constant acceleration of 1.40 m/s2. (a) How long in seconds does it take her to reach a speed of 2.20 m/s? (b)If she then brakes to a stop in 0.8s, what is her (constant) deceleration in m/s2
(a) 1.57 (b) 2.75
Solve the following problem using analytical techniques: Suppose you walk 16.5 m straight west and then 25.5 m straight north. How far are you from your starting point, and what is the compass direction of a line connecting your starting point to your final position? (If you represent the two legs of the walk as vector displacements A and B, as in the figure below, then this problem asks you to find their sum R = A + B. Give the direction in degrees north of west.) Magnitude: Direction:
Magnitude: 30.1 Direction: 57.1
Solve the following problem using analytical techniques: Suppose you walk 17 m straight west and then 24.5 m straight north. How far are you from your starting point, and what is the compass direction of a line connecting your starting point to your final position? (If you represent the two legs of the walk as vector displacements A and B, as in the figure below, then this problem asks you to find their sum R = A + B. Give the direction in degrees north of west.) Magnitude: Direction:
Magnitude: 29.8 Direction: 55.2
A ball is thrown horizontally from the top of a 57.0-m building and lands 105.3 m from the base of the building. Ignore air resistance. (Assume the ball is thrown in the +x direction and upward to be in the +y direction.) (a) How long (in s) is the ball in the air? (b) What must have been the initial horizontal component of the velocity (in m/s)? (Indicate the direction with the sign of your answer.)
(a) 3.41s (b) 30.79 or 30.87
A ball is thrown horizontally from the top of a 64.0-m building and lands 122.3 m from the base of the building. Ignore air resistance. (Assume the ball is thrown in the +x direction and upward to be in the +y direction.) (a) How long (in s) is the ball in the air? (b) What must have been the initial horizontal component of the velocity (in m/s)? (Indicate the direction with the sign of your answer.)
(a) 3.61 (b) 33.8
A 61.0 kg sprinter starts a race with an acceleration of 2.44 m/s2. What is the net external force (in N) on him? (Enter the magnitude.)
148.84
A 79.0 kg sprinter starts a race with an acceleration of 1.52 m/s2. What is the net external force (in N) on him? (Enter the magnitude.)
120.08
An 84.0 kg sprinter starts a race with an acceleration of 2.12 m/s2. What is the net external force (in N) on him? (Enter the magnitude.)
178.08
A cleaner pushes a 4.60 kg laundry cart in such a way that the net external force on it is 59.5 N. Calculate the magnitude of its acceleration (in m/s2).
13.02
A cleaner pushes a 4.10 kg laundry cart in such a way that the net external force on it is 62.5 N. Calculate the magnitude of its acceleration (in m/s2).
15.24
A cleaner pushes a 4.00 kg laundry cart in such a way that the net external force on it is 63.0 N. Calculate the magnitude of its acceleration (in m/s2).
15.8
A powerful motorcycle can accelerate from rest to 25.8 m/s (58 mi/h) in only 1.90s (a) What is its average acceleration in m/s2? (b) How far does it travel in that time?
(a) 13.6 (b) 24.5
A powerful motorcycle can accelerate from rest to 28.8 m/s (58 mi/h) in only 2.90s (a) What is its average acceleration in m/s2? (b) How far does it travel in that time?
(a) 9.93 (b) 41.8
A very strong, but inept, shot putter puts the shot straight up with an initial velocity of 10.0 m/s. How long does he have to get out of the way if the shot was released at a height of 2.20 m, and he is 1.70 m tall (he could end up shorter)?
Answer: 2.09s
An arrow is shot from a height of 1.4 m toward a cliff of height H. It is shot with a velocity of 25 m/s at an angle of 60° above the horizontal. It lands on the top edge of the cliff 3.4s later (a). What is the height of the cliff? (b). What is the max height reached by the arrow along its trajectory?
(a) 18.4 (b) 25.3
An arrow is shot from a height of 1.7 m toward a cliff of height H. It is shot with a velocity of 29 m/s at an angle of 60° above the horizontal. It lands on the top edge of the cliff 3.6 s later (a). What is the height of the cliff? (b). What is the max height reached by the arrow along its trajectory?
(a) 28.6 (b) 33.9
A very strong, but inept, shot putter puts the shot straight up with an initial velocity of 11.0 m/s. How long does he have to get out of the way if the shot was released at a height of 2.30 m, and he is 1.70 m tall (he could end up shorter)?
Answer: 2.3s