Explanation:
distance and time both are scaler quantity
Is there supposed to be a picture?
The unconscious mind plays a large role in Sigmund Freud's psychoanalysis<span>. He discussed the importance of the unconscious mind in understanding conscious thought and behaviour. </span><span>Sigmund Freud
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Answer:
This is known as a Galilean transformation where
V' = V - U
Where the primed frame is the Earth frame and the unprimed frame is the frame moving with respect to the moving frame
V - speed of object in the unprimed frame
U - speed of primed frame with respect to the unprimed frame
Here we have:
V = -15 m/s speed of ball in the moving frame (the truck)
U = -20 m/s speed of primed (rest) frame with respect to moving frame
So V' = -15 - (-20) = 5 m/s
It may help if you draw a vector representing the moving frame and then add
a vector representing the speed of the ball in the moving frame.