8. An object travels as the description shown below.

From t = 0 s to t = 7 s, the object was travelling with a constant velocity of 20 m/s. From t = 7 s to t = 11 s, it underwent a constant acceleration and reached a final velocity of 40 m/s at t = 11 s. The object is travelling to the right for the entire motion.
a) What was the acceleration of the object at t = 8 s?
b) What was the value of t when the object’s speed was 28 m/s?

Question

8.	An object travels as the description shown below.
	
From t = 0 s to t = 7 s, the object was travelling with a constant velocity of 20 m/s. From t = 7 s to t = 11 s, it underwent a constant acceleration and reached a final velocity of 40 m/s at t = 11 s.  The object is travelling to the right for the entire motion.
a)	What was the acceleration of the object at t = 8 s?
b)	What was the value of t when the object’s speed was 28 m/s?

anonymous · Answer

it would be easy to solve these type of problem using velocity-time diagram

anonymous · Answer

Ya, but he thing is I do not know how to draw the diagram

ganeshie8 · Answer

it sats acceleration is constant, so from t=7 to t= 11, a is same

t = 11-7 = 4 s

v = u+ at
40 = 20 + a(4)
=> a= ?

ganeshie8 · Answer

*says

anonymous · Answer

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