The minimum power required to lift a mass of 50 kg up to a vertical distance of 8 m in 10 s is: (Take g = 10 m/s²)
400 W
Using the formula for work done: Work = mgh
Work = 50 × 10 × 8 = 4000 J
Power = Work/Time = 4000 J / 10 s = 400 W.
The minimum power required is 400 W, so the correct answer is (a) 400 W.
A metallic sphere of mass 1 kg and volume 2 × 10-4 m³ is completely immersed in water. The buoyant force exerted by water on the sphere is:
A body floats in a liquid if the buoyant force is:
A motorcycle has an initial velocity of 5 m/s. After 3 seconds, the velocity is 7 m/s. The displacement of the motorcycle in 3 seconds is:
The force with which the Earth attracts an object is called:
What special name is given to the frictional force exerted by a fluid?
______ is used in periscope.
Zero degree centigrade is equal to what degree Fahrenheit?
A. 100°F
B. 30°F
C. 34°F
D. 32°F
Keeping voltage constant, if more lamps are put into a series circuit, the overall current in the circuit:
A. Increases
B. Decreases
C. Remains the same
D. Becomes infinite
Excessive curvature of eye lens leads to _______