Explanation

To find the speed, we can use the formula:

Speed = Distance / Time

Given:

Distance = 150 meters

Time = 5 seconds

Speed = 150 / 5

Speed = 30 m/s

So, the cycling speed of the girl is 30 meters per second.

Explanation

• Force is the only option that can change an object's speed.
• According to Newton's second law of motion, force is directly related to an object's acceleration, which is the change in speed over time.

Explanation

• Laboratory thermometers typically have a lower temperature range than clinical thermometers, and are designed to measure temperatures in a laboratory setting.
• The lowest temperature in a laboratory thermometer is often around -10°C or even lower, depending on the specific thermometer.

Explanation

When handling a clinical thermometer, you should:

• Wash it before use (to ensure cleanliness and accuracy)
• Stay at one place (to avoid moving around and potentially breaking the thermometer)
• Place it in a cover after use (to protect the thermometer from damage and contamination)

But you should not Run while handling a clinical thermometer, as this could cause the thermometer to break or become damaged.

Explanation

Force can change an object's:

• Direction (by changing its trajectory)
• Size (by compressing or expanding it)
• Speed (by accelerating or decelerating it)

But force cannot change an object's mass.

Mass is a fundamental property of an object that remains constant, regardless of the forces acting upon it.

Explanation

A force is a Push or a Pull that causes movement.

Explanation

Focus is the point where the parallel beam of light rays originating from a point on the object converges.

Explanation

If mass of bob of simple pendulum increase its time period will unaffected.

As time period only depends only depends upon length of pendulum and acceleration due to gravity at that position.

$T=\sqrt[2\pi ]{2\pi \frac{l}{g}}$

$T$ = time period

$l$= length of pendulum

$g$= Acceleration at the position of simple pendulum.

Explanation

The minute hand of a clock moves 360 degrees (or 2π radians) in 60 minutes, which is equivalent to 1 hour.

To find the angular velocity, we can use the formula:

ω = Δθ / Δt

where ω is the angular velocity, Δθ is the change in angle (2π radians), and Δt is the time (1 hour or 3600 seconds).

Plugging in the values, we get:

ω = 2π radians / 3600 s ≈ 0.00175 rad s⁻¹

So, the angular velocity of the minute hand is approximately 0.00175 rad s⁻¹.

Explanation

• When the frequency of the modulated wave is less than the frequency of the carrier wave, it indicates that the input signal is negative.
• This is a characteristic of amplitude modulation (AM) where the input signal is negative, resulting in a decrease in the amplitude of the carrier wave.