Distance travelled with constant velocity or constant acceleration

[Physics1854]

Homework Statement

A cyclist is traveling along a straight horizontal road. as she passes a bus stop she sees a red traffic light ahead of her. She continues to travel with a constand speed of 3 ms^-1 for 20 seconds and then decelerates at a constant rate of 0.2ns^-2 until coming to rest at the traffic light

Homework Equations

a) calculate the distance between the bus stop and the traffic light

b) calculate the time the cyclist takes to travel from the bus stop to the traffic light

c) calculate the average speed of the cyclist between the bus stop and the traffic light

The Attempt at a Solution

 

[rl.bhat]

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