Answer:
acceleration or a deceleration
Explanation:
The gradient of a position - time graph represent the velocity.
a straight line indicate a constant velocity (gradient ≠ 0)
when it is a parallel line to the time axis , it indicated no movement
when it is a curved line it indicates a changing velocity (either acceleration or a deceleration) as mentioned in the graph
No, sound waves are invisible to our eyes
I think C and D are the best way to describe projectile motion since both left the ground and stayed aloft for a small or large amount of time. A and B are example of motion but not projectile
Explanation:
Initial velocity is 25m/s i.e. u. Final velocity would be zero since the bus stopped. It is noted that the bus deccelartion of 4m/s, so the acceleration should be considered negative of 4m/s I.e. 4m/s. So using third law of motion i.e.
v^2 - u^2= 2as
(0)^2 - (25)^2= -2×4×s {Note here I used minus sign in acceleration}
-625 = -8×s
s=625 ÷ 8
s= 125 m
So bus would cover a distance of 125m before coming to rest.
Machine C. Machine A has an efficiency of 250/1000 = 0.25 = 25%, Machine B's efficiency is 350/500 = 0.7 = 70% and Machine C has an efficiency of 150/200 = 0.75 = 75%.
