Explanation

For the X and Y components of a force to be equal:

Fx = Fy

Given F = Fx i + Fy j = F cos(θ) i + F sin(θ) j

Fx = F cos(θ)

Fy = F sin(θ)

For Fx = Fy:

F cos(θ) = F sin(θ)

cos(θ) = sin(θ)

tan(θ) = 1

θ = 45°

Explanation

The orbital speed (v) of a satellite is given by:

v = √(GM / (R + h))

If the orbital radius (R + h) is halved:

v' = √(GM / ((R + h) / 2))

= √(2GM / (R + h))

= √2 * √(GM / (R + h))

= √2 * v

So, the orbital speed will increase √2 times.

Explanation

The relation between the coefficient of volume expansion (γ) and the coefficient of linear expansion (α) is: γ = 3α

This relation holds true for isotropic solids.

The coefficient of volume expansion is approximately three times the coefficient of linear expansion.

Explanation

The turns ratio of a transformer is given by:

n = N₂ / N₁ = V₂ / V₁

Where:

- n is the turns ratio

- N₁ and N₂ are the number of turns in the primary and secondary coils

- V₁ and V₂ are the primary and secondary voltages

Given n = 5:

V₂ / V₁ = 5

This means the secondary voltage is greater than the primary voltage by a factor of 5.

Explanation

To find the pressure, we use the formula:

P = F / A

Where:

- P is the pressure

- F is the force (weight) = 392 N

- A is the area = 0.0001 m²

P = 392 N / 0.0001 m² = 3,920,000 Pa

To convert Pascals (Pa) to Megapascals (MPa):

3,920,000 Pa = 3.92 MPa

Explanation

The energy density (u) in a capacitor is given by:

u = ½ε₀E²

Where:

- ε₀ is the permittivity of free space

- E is the electric field intensity between the plates

This shows that the energy density is proportional to the square of the electric field intensity (E²).

Explanation

The relation between work (W) done and torque (τ) in rotational motion is:

W = τdθ

Where:

- W is the work done

- τ is the torque

- dθ is the angular displacement

This shows that work done in rotational motion is the product of torque and angular displacement.

Explanation

e/m = 2E/B²r²

The formula is derived by equating the magnetic Lorentz force to the centripetal force and using the kinetic energy gained from the accelerating voltage E.

This formula correctly relates the charge-to-mass ratio of an electron to the magnetic field B, radius of the circular path r, and accelerating voltage E.

Explanation

For a polyatomic gas, Cv is typically 3R, accounting for translational and rotational degrees of freedom.

This value can increase with temperature as vibrational modes become excited, contributing to the specific heat.

Explanation

When an object is placed at the principal focus (F) of a convex lens, the rays emerge parallel after refraction.

Parallel rays appear to meet at infinity, so the image is formed at infinity (very far away).