Tahsili Physics 2

Question 1

What is Newton's Third Law of Motion?

Accepted Answer

For every action, there is an equal and opposite reaction

Answer

Newton's Third Law states that when object A exerts a force on object B, object B simultaneously exerts an equal and opposite force on object A. These action-reaction pairs act on different objects.

Question 2

A projectile is launched at 45° with an initial velocity of 20 m/s. What is the horizontal component of velocity?

Accepted Answer

20/√2 ≈ 14.14 m/s

Answer

Horizontal component: vₓ = v₀cos(45°) = 20 × cos(45°) = 20 × (√2/2) = 20/√2 ≈ 14.14 m/s. At 45°, both horizontal and vertical components are equal.

Question 3

What is the total resistance of three resistors (2Ω, 3Ω, 6Ω) connected in parallel?

Accepted Answer

1 Ω

Answer

For parallel: 1/R = 1/2 + 1/3 + 1/6 = 3/6 + 2/6 + 1/6 = 6/6 = 1. Therefore R = 1Ω. Parallel resistance is always less than the smallest individual resistor.

Question 4

What happens to the gravitational force between two objects if the distance between them is doubled?

Accepted Answer

It becomes one-quarter

Answer

Gravitational force follows the inverse square law: F = Gm₁m₂/r². If r doubles (2r), F = Gm₁m₂/(2r)² = Gm₁m₂/4r² = F/4. The force becomes one-quarter of the original.

Question 5

What is the principle of conservation of momentum?

Accepted Answer

In an isolated system, total momentum before a collision equals total momentum after

Answer

Conservation of momentum states: in an isolated system (no external forces), total momentum is constant. m₁v₁ + m₂v₂ = m₁v₁' + m₂v₂'. This applies to ALL collisions (elastic and inelastic) and is fundamental to the Tahsili physics section.

Tahsili Practice Test

Tahsili Practice Test

Tahsili Physics 2