NSAA NSAA Physics - Mechanics

Question 1

A ball is thrown vertically upward with an initial velocity of 20 m/s. What is the maximum height reached (g = 10 m/s²)?

Accepted Answer

20 m

Answer

Using v² = u² - 2gh, with v=0 at maximum height: h = u²/2g = 400/20 = 20 m.

Question 2

A 5 kg block slides down a frictionless incline of 30°. What is its acceleration?

Accepted Answer

4.9 m/s²

Answer

The component of gravity along the incline is g sin30° = 9.8 × 0.5 = 4.9 m/s².

Question 3

Two objects of mass 3 kg and 5 kg collide and stick together. If the 3 kg object was moving at 8 m/s and the 5 kg was stationary, what is the final velocity?

Accepted Answer

3 m/s

Answer

By conservation of momentum: 3×8 = (3+5)v, so v = 24/8 = 3 m/s.

Question 4

A car of mass 1000 kg accelerates from rest to 20 m/s in 10 s. What net force acts on it?

Accepted Answer

2000 N

Answer

Acceleration = 20/10 = 2 m/s²; F = ma = 1000 × 2 = 2000 N.

Question 5

A spring of spring constant 200 N/m is compressed by 0.05 m. What is the elastic potential energy stored?

Accepted Answer

0.25 J

Answer

Elastic PE = ½kx² = ½ × 200 × (0.05)² = 0.25 J.

NSAA - Natural Sciences Admissions Assessment Practice Test

NSAA - Natural Sciences Admissions Assessment Practice Test

NSAA NSAA Physics - Mechanics