A body of mass 2kg is suspended from the ceiling of a lift with a light inextensible string. lf the lift moves upwards with acceleration of 2ms-2, calculate...
A body of mass 2kg is suspended from the ceiling of a lift with a light inextensible string. lf the lift moves upwards with acceleration of 2ms-2, calculate the magnitude of the tension in the string (g = 1Oms-2)
Answer Details
When a body of mass is suspended by a string, the tension in the string is equal to the weight of the body.
The weight of the body is given by the formula:
Weight = mass x gravity
where "mass" is the mass of the body and "gravity" is the acceleration due to gravity.
In this case, the mass of the body is 2 kg and the acceleration due to gravity is 10 m/s^2.
However, the lift is accelerating upwards with an acceleration of 2 m/s^2. This means that the net acceleration of the body (relative to the lift) is the difference between the acceleration due to gravity and the acceleration of the lift:
Net acceleration = acceleration due to gravity - acceleration of the lift
Net acceleration = 10 m/s^2 - 2 m/s^2
Net acceleration = 8 m/s^2
Therefore, the net force acting on the body (relative to the lift) is given by the formula:
Net force = mass x net acceleration
Substituting the given values, we have:
Net force = 2 kg x 8 m/s^2
Net force = 16 N
Since the tension in the string is equal to the net force acting on the body, the tension in the string is 16 N.
Therefore, the correct answer to the question is "16N".