Advertisements
Advertisements
प्रश्न
Give scientific reason for the following:
Passengers in a bus are pushed backward when it starts suddenly.
उत्तर
This is due to the fact that the body of the passenger is in the state of rest as long as the bus is at rest. When the bus starts, his feet acquire the velocity of the bus and come to motion with the moving bus, while the upper portion of his body due to inertia of rest tends to remain in the state of rest, resulting in his tendency to fall backwards.
APPEARS IN
संबंधित प्रश्न
Answer the following.
What is a machine?
Answer the following in short.
Mention any two methods by which we can take care of machines.
Give a reason for the following.
Machines are able to make our work convenient.
show a nut cracker In the diagram, mark the position of the fulcrum F and the line of action of load L and effort E .
Can a machine be 100% efficient?
Fig. shows a spade. It is being used to lift soil weighing 30N from the ground.
(a) Mark the direction of the least force on the handle necessary to keep the spade balanced.
(b) Calculate the least force on the handle necessary to keep the spade balanced (the weight of the spade is negligible).
(c) If the left hand was move towards the soil on the spade, would the force on the handle necessary to keep the soil balance the greater or less? Give a reason for your answer.
(d) To which class of lever does the spade belong?
What is the efficiency of an ideal machine?
Which machine will you use to do the following work? Write their type.
To cut vegetables.
Why is this so machines have to be maintained?
The idea of a simple machine originated with the Greek philosopher Archimedes.
