Answer:
There are three ways an object can accelerate: a change in velocity, a change in direction, or a change in both velocity and direction.
Explanation:
For the object to be moving, there must be a value for the forces acting on this object in a certain direction to cause the object to move.
On the other hand, when an object is at rest, despite the possibility of having several forces acting on it, these forces balance out to a net force of zero which keeps the body still with no motion.
Explanation:
Initial speed of blood, u = 0
Final speed of the blood, v = 26 cm/s
(a) Displacement of the blood, d = 2 cm
Let a be its acceleration. It can be calculated using third equation of motion as :



(b) Let t is the time taken by the blood to reach its final speed. It can be calculated as :
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t = 0.15 s
Hence, this is the required solution.
Answer:
B
Explanation:
Acceleration = rate of change in velocity
a = (21-12)/(0.45) = 20cm/s^2