Answer: T= 715 N
Explanation:
The only external force (neglecting gravity) acting on the swinging mass, is the centripetal force, which. in this case, is represented by the tension in the string, so we can say:
T = mv² / r
At the moment that the mass be released, it wil continue moving in a straight line at the same tangential speed that it had just an instant before, which is the same speed included in the centripetal force expression.
So the kinetic energy will be the following:
K = 1/2 m v² = 15. 0 J
Solving for v², and replacing in the expression for T:
T = 1.9 Kg (3.97)² m²/s² / 0.042 m = 715 N
Answer:
30 kilometers per hour.
Explanation:
we know this by dividing 60 by 2
The answer is C. Electrical;mechanical
Answer:
Specific heat of liquid 
Explanation:
We know in thermal equilibrium :
Loss in heat by iron block = Gain in heat by liquid .
Specific heat of iron = 0.45 
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Now , loss in heat by iron block = 
Heat gain by liquid=
Equating both we get :
