Resonance occurs when a force causes an object to vibrate at

Its natural frequency

Explanation:

Resonance occurs when a force causes an object to vibrate. The object has a higher probability of doing so at a specific rate called the object's natural frequency or resonant.

The frequency is dependent on the size, shape, and composition and properties of the object involved.

Resonance occurs when a force causes an object to vibrate at

its own natural frequency

Explanation:

What is resonance .

This is a phenomenon in which an external force or a vibrating system forces another system around it to vibrate with greater amplitude at a specified frequency of operation.

When an object is forced to vibrate at its natural frequency, resonance occurs. Sound can travel through solids, liquids, gases, and even a vacuum. In order for sound from a speaker to reach a listener, air near the speaker must travel to the listener

What is a forced vibration?

Forced vibration is a type of vibration in which a force is repeatedly applied to a mechanical system.

Forced vibration is when an alternating force or motion is applied to a mechanical system.

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s