Explanation

To find the moment of inertia (I) of the rotating body, we can use the formula:

τ = I × α

where τ is the torque, I is the moment of inertia, and α is the angular acceleration.

Given:

τ = 2 × 10^-4 Nm

α = 4 rad/s^2

Rearranging the formula to solve for I:

I = τ / α

= (2 × 10^-4 Nm) / (4 rad/s^2)

= 0.5 × 10^-4 kgm^2

Explanation

To boil 1 liter of water from 15°C to 100°C, the energy required is:

Q = mcΔT

= 1 kg × 4.18 kJ/kg°C × (100°C - 15°C)

= 1 × 4.18 × 85

= 355 kJ

Explanation

Explanation

Explanation

Explanation

Swimming is a full-body workout that engages multiple muscle groups.

It leading to high energy expenditure.

It is often considered more energy-intensive than jogging, riding, or running due to the resistance of water.

Explanation

The photoelectric effect does not occur if the frequency of the incident light is below the threshold frequency.

The threshold frequency is the minimum frequency required for the incident photons to have enough energy to eject electrons from the surface of the material.

If the frequency is below this value, no electrons are emitted, regardless of the light intensity.

Explanation

The SI unit of work is the joule (J), which is the same unit used for energy. 

Explanation

The cross product (A × B) is a vector whose magnitude is given by:

| A × B | = |A||B| sinθ

Its direction follows the right-hand rule.

Explanation

73.650 rounded up to one decimal place is 73.7.

When rounding up, if the digit to the right of the desired decimal place is 5 or greater,

You increase the digit in the desired decimal place by one.

Since 5 in the hundredth place is greater than or equal to 5, the tenths place digit (6) is increased to 7.