16. A pump is used to pump a liquid of density? continuously through a pipe of cross-section area A. If a liquid is flowing with speed V, then the power of the pump is?
- 1/3 ρAv²
- 1/2 ρAv²
- 2ρAv²
- 1/2 ρAv³
17. A car of mass m has an engine that can deliver power P. The minimum time in which car can be accelerated from rest to a speed v is?
- mv²/2P
- Pmv²
- 2Pmv²
- mv²P/2
18. From a waterfall, water is pouring down at the rate of 100 kg/s, on the blades of a turbine. If the height of the fall is 100 m, the power delivered to the turbine is approximately equal to?
- 100 kW
- 10 kW
- 1 kW
- 100 W
19. A particle of mass 200 g is moving in a circle of radius 2 m. The particle is just ‘looping the loop’. The speed of the particle and the tension in the string at the highest point of the circular path are (g = 10 m/s²)-
- 4 m/s, 5 N
- 4.47 m/s, zero
- 2.47 m/s, zero
- 1 m/s, zero
20. A particle of mass 200 gram, is whirled into a vertical circle of radius 80 cm using a massless string. The speed of the particle when the string makes an angle of 60° with the vertical line is 1.5 m/s. The tension in the string at this position is?
- 1 N
- 1.56 N
- 2 N
- 3 N