Explanation

Momentum is the product of an object’s mass and its velocity → Momentum = Mass × Velocity.

Momentum is given by the formula: p = mv

It is a vector quantity.

It is conserved in closed systems during collisions.

It depends on mass and speed, not on acceleration, so momentum is independent of acceleration.

Explanation

A tuning fork is specifically designed to vibrate at a specific frequency,

And it resonates when struck, producing a sound wave at that particular frequency

Explanation

Solution for Total Time of Flight of a Projectile:

Given:  

- Initial velocity = u  

- Angle of projection = θ  

- Acceleration due to gravity = g  

When a projectile is launched, it moves upward and then comes back down under gravity.

- The vertical component of velocity = u sin θ  

- The time to reach the highest point (where vertical velocity = 0) is:  

  t = (u sin θ) / g  

- Total time of flight is twice the time to reach the highest point (because time going up = time coming down), so:  

  T = 2 × (u sin θ) / g = (2u sin θ) / g  

Explanation

1 kilowatt-hour (kWh) is equal to the energy consumed by an apparatus working at a power of 1 kilowatt (kW) for 1 hour.

1 kW is equal to 1000 watts (W), and 1 hour is equal to 3600 seconds (s).

So, to convert from kWh to joules (J), we have: 1 kWh = 1000 W × 3600 s

We know that 1 W = 1 J/s, so: 1 kWh = (1000 J/s) × 3600 s

Now we can cancel out the seconds (s): 1 kWh = 1000 J × 3600

Multiplying the numbers together, we get: 1 kWh = 3,600,000 J = 3.6 × 10⁶ J

Finally, since 1 MJ = 10⁶  J; 1 kWh = 3.6 MJ

Explanation

A galvanometer measures small currents.

To measure larger currents, a low resistance (called a shunt) is connected in parallel, converting it into an ammeter.

Explanation

In an astronomical telescope, the objective lens has a very large focal length (to gather distant light) and the eyepiece has a short focal length (to magnify the image)

In an astronomical telescope:  

- The objective lens has a long focal length (to gather light and form the image)  

- The eyepiece lens has a short focal length (to magnify the image)  

Hence, 1000 cm (objective) and 10 cm (eyepiece) is typical.

Explanation

Permittivity (ε) quantifies how much the electric field is reduced within a medium.  

Its SI unit is Farad per meter (F/m).

Explanation

 A chair and a Table are pieces of furniture.

- Car is a vehicle, not furniture.

So, the Car is different from the rest.

Explanation

The orbit of a satellite depends on the gravitational force, which is determined by the mass of Earth, the gravitational constant, and the radius of the orbit.

The mass of the satellite cancels out during derivation (e.g., in centripetal force = gravitational force), so it does not affect the orbital path.

Explanation

In a step-down transformer, the number of turns in the primary coil (NP) is greater than that in the secondary coil (NS) to reduce the voltage.