Advertisements
Advertisements
प्रश्न
Fill in the blank with suitable word :
1 joule is the work done when a force of 1 __________ moves an object through a distance of one __________ in the direction of __________.
Advertisements
उत्तर
1 joule is the work done when a force of 1 Newton moves an object through a distance of one meter in the direction of force.
APPEARS IN
संबंधित प्रश्न
When do we say that work is done?
Write an expression for the work done when a force is acting on an object in the direction of its displacement.
Differentiate between energy and power.
Is work a scalar or a vector quantity?
What happens to the work done when the dispacement of body is at right angles to the direction of force acting on it? Explain your answer.
State the energy changes which take place when An electric bulb glows when it is connected to a source of electric current.
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?
Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
A green plant is carrying out photosynthesis.
A uniform chain of length 2 m is kept on a table such that a length of 60 cm hangs freely from the edge of the table. The total mass of the chain is 4 kg. What is the work done in pulling the entire chain on the table?
