The image formed by a plane mirror is virtual, upright and the same size with the actual object. The upright image of an object in a plane mirror is can be found on the other side of the mirror which is why it is also virtual.
Answer:
The right answer is:
(a) 63.83 kg
(b) 0.725 m/s
Explanation:
The given query seems to be incomplete. Below is the attachment of the full question is attached.
The given values are:
T = 3 sec
k = 280 N/m
(a)
The mass of the string will be:
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or,
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On substituting the values, we get
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⇒ 
⇒ 
(b)
The speed of the string will be:
⇒ 
then,
⇒ 
On substituting the values, we get
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⇒ 
⇒ 
⇒ 