Advertisements
Advertisements
प्रश्न
Two coolies A and B do some work in time 1 minute and 2 minute respectively. The power spent is
विकल्प
same by both coolies
is more by coolie A than by B
is less by coolie A than by B
nothing can be said.
उत्तर
is more by coolie A than by B
APPEARS IN
संबंधित प्रश्न
A family uses 8 kW of power.
- Direct solar energy is incident on the horizontal surface at an average rate of 200 W per square meter. If 20% of this energy can be converted to useful electrical energy, how large an area is needed to supply 8 kW?
- Compare this area to that of the roof of a typical house.
1 H.P. = .........
A pump raises water by spending 4×105J of energy in 10s. Find the power of the pump.
Define power.
Arrive at an expression for power and velocity. Give some examples for the same.
A bullet of mass 20 g strikes a pendulum of mass 5 kg. The centre of mass of the pendulum rises a vertical distance of 10 cm. If the bullet gets embedded into the pendulum, calculate its initial speed.
Water falls from a height of 60 m at the rate of 15 kg/s to operate a turbine. The losses due to frictional force are 10% of the input energy. How much power is generated by the turbine? (g = 10m/s2)
The average work done by a human heart while it beats once is 0.5 J. Calculate the power used by heart if it beats 72 times in a minute.
Calculate the power spent by a crane while lifting a load of mass 2000 kg, at velocity of 1.5 ms-1. (g = 10 ms-2)
Name the quantity which is measured in kW.
