ECAT MCQs

Integrating velocity over time gives displacement.
Areas below the time axis count as negative displacement.

Average speed uses total distance.
400/80 = 5 m/s.

Uniform acceleration means velocity changes by equal amounts in equal times.
The standard kinematic equations apply.

The runner returns to the starting point, so displacement is zero.
Average velocity is therefore zero.

Inertia is related to mass.
Greater mass means greater resistance to acceleration.

Use v=u+at with u=0.
V=0+3×4 = 12 m/s.

The first law describes inertia.
A net external force is required to change velocity.

Use v=u+at.
V=5+2×6 = 17 m/s.

For constant mass, Newton's second law becomes F=ma.
It links net force to acceleration.

Acceleration is change in velocity divided by time.
(5-20)/3 = -5 m/s².

Interaction forces occur in pairs on different bodies.
They are equal in magnitude and opposite in direction.

Use s=ut+½at² with u=0.
S=½×2×25 = 25 m.