Question

As a train accelerates away from a station, it reaches a speed of 4.6 m/s in 5.2 s.

If the train's acceleration remains constant, what is its speed after an additional 7.0 s has elapsed? Express your answer using two significant figures.

2) The position of a car as a function of time is given by x=(60m)+(−4.0m/s)t+(−8m/s2)t2.

What is the initial position of the car?

Express your answer to two significant figures and include appropriate units.

3)A model rocket rises with constant acceleration to a height of 3.4 m, at which point its speed is 28.0 m/s.

Part A

How much time does it take for the rocket to reach this height?

Express your answer using two significant figures.

Part B

What was the magnitude of the rocket's acceleration?

Express your answer using two significant figures.

Part C

Find the height of the rocket 0.15 s after launch.

Express your answer using two significant figures.

Part D

Find the speed of the rocket 0.15 s after launch.

Express your answer using two significant figures.

Please help me with all these questions i know its alot but please

Answer 1

I Acceleration of train in first introds 5.2 se v=4 tal- 4.60 -a =) a = 4b = 0.8846 mine? 5.2 sp speed, v=ut at v=4.6 +0.8846X7.0 V= 10.79 ulice V = 11.00 mi see ② X= 60m+ (-4.0 m/s) t+(-8 m/s2) 4² at t=o. x = 60 - 400 - 6xo X = 60.00 m