1. The tolerance its 1+- in the 2nd significant digit

A train started from rest and moved with constant acceleration. At one time it was traveling 34 m/s, and 170 m farther on it was traveling 41 m/s. Calculate (a) the acceleration, (b) the time required to travel the 170 m mentioned, (c) the time required to attain the speed of 34 m/s, and (d) the distance moved from rest to the time the train had a speed of 34 m/s. (a) Number i Units (b) Number i Units (c) Number i Units (d) Number UnitsCurrent Attempt in Progress A hot rod can accelerate from O to 60 km/h in 7.4 s. (a) What is its average acceleration, during this time? {b} How far will it travel during the 7.4 5, assuming its acceleration is constant? {c} From rest, how much time would it require to go a distance of 0.21 km if its acceleration could be maintained at the value in {a}? (a) Number n Units v (b) Number n Units v (c) Number n Units v A model rocket red vertically from the ground ascends with a constant vertical acceleration of 48.7 m/s2 for 1.41 5. Its fuel is then exhausted. so it continues upward as a free-fall particle and then falls back down. {a} What is the maximum altitude reached? (b) What is the total time elapsed from takeoff until the rocket strikes the ground? (a) Number n Units v (b) Number n Units v A ball of moist clay falls 19.1 rn to the ground. It is in contact with the ground for 19.0 ms before stopping. (a) What is the average acceleration of the ball during the time it is in contact with the ground? (Treat the ball as a particle.) (b) Is the average acceleration up or down? (a) Number n Units v (bl v If the position of an object is given by x = 2.30t4, where x is measured in meters and t in seconds, find (a) the average velocity and (b) the average acceleration between t = 1.0s and t = 2.0 s. Then find (c) the instantaneous velocity v and (d) the instantaneous acceleration a at t = 1.0 s. Next find (e) v and (f)a at t = 2.0 s. (a) Number Units (b) Number i Units (c) Number i Units (d) Number Units (e) Number Units (f) Number i Units vTwo trains, each having a speed of 37 km/h, are headed at each other on the same straight track. A bird that can fly 74 km/h flies off the front of one train when they are 74 km apart and heads directly for the other train. On reaching the other train it flies directly back to the first train, and so forth. (We have no idea why a bird would behave in this way.) What is the total distance the bird travels? Number UnitsCurrent Attempt in Progress (a) Ifthe maximum acceleration that is tolerablefor passengers in a subway train is 1.44 m/s2 and subway stations are located 826 m apart, what is the maximum speed a subway train can attain between stations? (b) What is the travel time between stations? ((1) If a subway train stops for 22.0 s at each station. what is the maximum average speed of the train, from one start-up to the next? (a) Number n Units v (b) Number n Units v (c) Number n Units v From t : 0 to t = 4.46 min, a man stands still, and from t = 4.46 min tot = 8.92 min. he walks briskly in a straight line at a constant speed of 2.39 m/s. What are (a} his average velocity v3\Current Attempt in Progress In 1 km races, runner 1 on track 1 (with time 2 min, 20.51 5) appears to be faster than runner 2 on track 2 {2 min. 20.69 5}. However, length L2 of track 2 might be siightly greater than length L1 01' track 1. How large can L2 - L1 be for us to conclude that runner 1 is faster? Number n Units v Current Attempt in Progress In an arcade video game, a spot is programmed to move across the screen according to x = 7.10t - 0.648ts, where x is the distance in centimeters measured from the left edge of the screen and t is time in seconds. When the spot reaches a screen edge, either at x = 0 or x = 11.0 cm, t is reset to O and the spot starts moving again according to x(t). (a) At what time after starting is the spot instantaneously at rest? (b) At what value of x does this occur? (c) What is the spot's acceleration when this occurs? (d) At what time t > 0 does the spot first reach an edge of the screen? (a) Number Units (b) Number i Units (c) Number i Units (d) Number i Units V