Home
Class 10
PHYSICS
A machine is driven by a 100 kg mass tha...

A machine is driven by a 100 kg mass that falls `8m` in `4*0`s. it lifts a load of mass 500 kg vertically upwards. Taking `g=10ms^(-2)`. Calculate:
(a) the force exerted by the falling mass.
(b) the work done by the falling mass in its displacement by `8*0`m.
(c) the power input to the machine.
(d) the power output of the machine if its efficiency is 60%, and
(e) the work done by the machine is `4*0`s.

Text Solution

Verified by Experts

Given: `m=100kg,d=8*0m,t=4*0s,L=500kg`
(a) Force exerted by the falling mass=mg
`=100xx10=1000N`
(b) Work done by the falling mass
=force exerted by the falling mass`xx`displacement
`=mgxxd`
`=1000xx8*0=8000J`
(c) Power input`=("work done on machine")/("time")`
`=(8000J)/(4*0s)=2000W`
(d) Given, efficiency=60%=`0*6`
power input=?
Since efficiency=`("power input")/("power input")`
`therefore`Power output=power input`xx`efficiency
`=2000Wxx0*6=1200W`
(e) Work done by the machine is `4*0`s
=power output `xx` time
`=1200Wxx4*0s=4800J`.
Promotional Banner

Topper's Solved these Questions

  • MACHINES

    ICSE|Exercise EXERCISE-3(A)|40 Videos
  • MACHINES

    ICSE|Exercise EXERCISE-3(A) MULTIPLE CHOICE TYPE|5 Videos
  • HOUSEHOLD CIRCUITS

    ICSE|Exercise EXERCISE -9(B) (MULTIPLE CHOICE TYPE)|2 Videos
  • QUESTION PAPER 2022 TERM 1

    ICSE|Exercise MULTIPLE CHOICE QUESTIONS|40 Videos

Similar Questions

Explore conceptually related problems

A machine raises a laod a 750 N through a height of 16 m in 5 s.Calculate: (i)the energy spent by the machine , (ii)the power of the machine if it is 100 % efficient.

A crane pulls up a car of mass 500 kg to a vertical height of 4 m. Calculate the work done by the crane.

The power output of machine that lifts a 600 kg crate through a height of 20 m in 1 minute, is

A stone of mass 0.4 kg is projected vertically upward through a height 10 m. if g=10 ms^(-2) , calculate the potential energy of the stone at the highest point.

A fixed pulley is driven by a 100 kg mass falling at a rate of 8*0 m in 4*0s . It lifts a load of 75*0 kgf. Calculate (a) The power input to the pulley taking the force of gravity on 1 kg as 10 N. (b) the efficiency of the pulley, and (c) The height to which the load is raised in 4*0s .

For a system of pulleys, the mechanical advantage is 4. Taking g = 10m//s^(2) , the force required to lift a mass of 100 kg by it is

A boy mass 40 kg climbs up the stairs and reaches the roof at a height 8 m in 5 s. Calculate : (i)the force of gravity acting the boy . (ii) the work done by against the force of gravity . (iii)the power spent by the boy . (Take g=10 m S^(-2) )

A box of 50 kg is lifted by a man of mass 60 kg to a height of 50 m. Calculate the work done by the man.

Certain force acting on a 20 kg mass changes its velocity from 5m//s to 2m//s . calculate the work done by the force.

A helicopter lifts a body of mass 100kg to a height of 500m at a constant speed. It takes 5min to lift the body. Find the work done by the helicopter and the power required.