Physics
Fill in the blanks.
(a) The ratio of the load lifted by a machine to the effort applied on it is called …………… .
(b) Work done on an object is the product of …………… and …………… .
(c) There are three types of levers based on the positions of ……………, …………… and …………… .
(d) The ratio of work done by a machine to the work done on the machine is termed as …………… of the machine.
(e) The arrangement of several pulleys to pick heavy loads is called …………… .
Answer
(a) The ratio of the load lifted by a machine to the effort applied on it is called mechanical advantage.
(b) Work done on an object is the product of force and distance.
(c) There are three types of levers based on the positions of fulcrum, load and effort .
(d) The ratio of work done by a machine to the work done on the machine is termed as efficiency of the machine.
(e) The arrangement of several pulleys to pick heavy loads is called block and tackle system.
Related Questions
Solve the following numericals.
(a) What is the mechanical advantage of a machine that lifts a load of 100 N with an effort of 20 N?
(b) What is the effort required if the mechanical advantage is 9 and the load is 81 N?
Some of the facts that you have learnt till now are listed below. Tick (✓) the facts that are correct and cross (x) the facts that are incorrect.
(a) Efficiency of a machine can be 100%.
(b) A wheel and axle move together.
(c) A wedge is a combination of an axle and inclined plane.
(d) Screw acts as a fastener.
(e) Screwdriver is an example of screw.
State whether the following statements are true or false. Correct the false statements.
(a) A girl riding a bicycle is getting zero work done.
(b) When the value of mechanical advantage is equal to one, it means that effort is equal to load.
(c) In class III lever, the fulcrum is between the load and the effort.
(d) In a fixed pulley, the pulley can move.
(e) Tyres of cars and buses are examples of wheel and axle.
Which of the following is not a simple machine?
- Bicycle
- Scissors
- Doorknobs
- Bottle openers