Answer:
The tension in the string is quadrupled i.e. increased by a factor of 4.
Explanation:
The tension in the string is the centripetal force. This force is given by

m is the mass, v is the velocity and r is the radius.
It follows that
, provided m and r are constant.
When v is doubled, the new force,
, is

Hence, the tension in the string is quadrupled.
Answer:
17.82J
Explanation:
Kinetic energy = 1/2 mv^2
Given
Mass M = 0.45kg
Velocity v = 8.9m/s
Therefore,
K.E. = 1/2 x 0.45 x (8.9)^2
= 1/2 x 0.45 x (8.9 x 8.9)
= 1/2 x 0.45 x 79.21
Multiply through
= 35.6445/2
= 17.82J
The kinetic energy of the ball is 17.82J
Unlike acceleration and velocity, speed does not need to specify the direction of motion. Speed is a scalar quality.
Answer: P= mad/t or P=w/t so P= 300/6= 50 W
It a stage known as the "Main Sequence" stage. Stars achieve nuclear stability at this point and remain in this stage until the end of their lives.
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