Alight-rail commuter train accelerates at a rate of 1.35 m/s2. how long does it take to reach its top speed of 80.0 km/h, starting from rest? (b) the same train ordinarily decelerates at a rate of 1.65 m/s2. how long does it take to come to a stop from its top speed? (c) in emergencies the train can decelerate more rapidly, coming to rest from 80.0 km/h in 8.30 s. what is its emergency deceleration in m/s2?

a) 16.46 seconds.

b) 13.46 seconds

c) 2.67 m/s²

Explanation:

Acceleration = a = 1.35 m/s²

Final velocity = v = 80 km/h =

Initial velocity = u = 0

Equation of motion

Time taken to accelerate to top speed is 16.46 seconds.

Acceleration = a = -1.65 m/s²

Initial velocity = u = 80 km/h=

Final velocity = v = 0

Time taken to stop the train from top speed is 13.46 seconds

Initial velocity = u = 80 km/h=

Time taken = t = 8.3 s

Final velocity = v = 0

Emergency deceleration is 2.67 m/s²

answer: d. a cme increases the amount of energy in the solar wind

explanation:

coronal mass ejections, also called cmes, are large clouds of plasma and magnetic field that erupt from the sun. only when the cloud is aimed at earth will the cme hit earth and therefore cause impacts. high-speed solar wind streams come from areas on the sun known as coronal holes.

e

explanation:

there is no change in the electric potential energy as it is in rest on both conditions.