Explanation

The weight of a man in an elevator descending with an acceleration of 4.9 m/s² will become:

Let:

• Actual weight $W=mg$

• Acceleration due to gravity g=9.8m/s^2

• Acceleration of the elevator a=4.9m/s^2

When an elevator descends with acceleration $a$, the apparent weight becomes:

W′=m(g−a)

Substitute values:

W′=m(9.8−4.9)=m(4.9)
W′=1​/2×mg

So, the apparent weight becomes half of the actual weight.

Explanation

Angular frequency (ω) measures how quickly something moves through an angle in circular motion.

It's given by:

$$omega = frac{2pi}{T} = 2pi f$$

Where:

• $T$ = time period

• $f$= frequency

While it’s also used in oscillations, it is fundamentally defined from circular motion.

Explanation

The slope of a velocity-time graph gives the rate of change of velocity, which is acceleration.

At any instant, this slope shows the instantaneous acceleration.

Explanation

It is the longest distance covered by the object during projectile motion.

When the angle of projection is 45°, the maximum horizontal range is obtained.

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.

Explanation

To convert radians to degrees, you multiply the number of radians by 180/π. 100 radians multiplied by 180/π is approximately 5729.58 degrees, which rounds to 5730 degrees. 

Explanation

For a diatomic gas (like O₂ or N₂), the ratio of specific heats 𝐶𝑝/𝐶𝑣 is approximately 1.4.

This ratio is also known as the adiabatic index (γ).

It is used in thermodynamic processes.

Explanation

A carburetor uses the principle of Bernoulli's equation, which states that as the speed of a fluid increases, its pressure decreases.

In a carburetor, air flows through a constricted section called a venturi.

This increased airflow creates a lower pressure area, which then draws fuel from the fuel reservoir into the air stream, effectively mixing them. 

Explanation

Explanation

Sonar (Sound Navigation and Ranging) uses sound waves to detect and locate objects underwater.

It works by emitting sound pulses into the water

And listening for the echoes that bounce back from objects like submarines, fish, or the seafloor.

Sonar is commonly used in navigation, fishing, and underwater exploration.