English

If 60% of the Potential Energy Available in a Waterfall is Converted into Heat Energy, Find the Height of the Waterfall, When the Temperature Difference Between the Top and the Bottom of the Fall - Physics

Advertisements
Advertisements

Question

If 60% of the potential energy available in a waterfall is converted into heat energy, find the height of the waterfall, when the temperature difference between the top and the bottom of the fall is 0.210C (sp. Heat cap. Of water = 4200J/kgK).
Numerical
Advertisements

Solution

Given, Sp. heat capacity of water, s = 4200 J/KgK

Temperature difference, Δt = 0.21 °C

Let 'h' be the height of the waterfall and 'm' be the mass of water.

Then, P.E of the water = mgh

Given that, heat energy, H = 60% of P.E

or, 4200 x 0.21 = 0.6 x 10 x h 

or, h = `(4200 xx 0.21)/(0.6 xx 10) = 882/6` = 147 m

shaalaa.com
  Is there an error in this question or solution?
Chapter 1: Force, Work, Energy and Power - Exercise 5 [Page 60]

APPEARS IN

Frank Physics - Part 2 [English] Class 10 ICSE
Chapter 1 Force, Work, Energy and Power
Exercise 5 | Q 7 | Page 60

RELATED QUESTIONS

An electron emitter must have _____________ work function and ___________ melting point.


A boy weighing 25 kgf climbs up from the first floor at height 3 m above the ground to the third floor at height 9m above the ground. What will be the increase in his gravitational potential energy? (Take g = 10 N kg -1)


Fill in the blank with suitable word :
Work is measured as a product of __________ and __________


What is the work done on the earth by the gravitational force of the sun during its motion around the sun?

Distinguish between work and power.


Complete the following sentences:

 1 H.P. = ........ W.


A body is pivoted at a point. A force of 10 N is applied at a distance of 30 cm from the pivot. Find the moment of force about the pivot.

A body of mass 60 kg has the momentum 3000 kgm/s-1. Calculate:  the speed of the body.


A truck driver can load oil drums into the back of the truck by pushing them up a sloping plank, or by lifting them directly. Each drum has a mass of 80 kg, the plank is 3 m long, and the back of the truck is 0.8 m above the ground.

(i) How much force would be needed to lift a drum into the truck directly/without using the plank? (Take g = 10 m/s2)

(ii) How much energy would be required in lifting the drum into the truck without the plank?

(iii) If the force needed to push the drum up the plank is 300 N, why is this less than the answer to part (i)?

(iv) When the truck is loaded, the driver drives off. List the major energy changes that take place in moving the truck.

(v) The driver has to stop at the factory gates. What happens to the kinetic energy of the truck?


A force is applied on a body of mass 20 kg moving with a velocity of 40 ms−1. The body attains a velocity of 50 ms−1 in 2 seconds. Calculate the work done by the body.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×