A train of mass 2-0- 105 kg has a constant speed of 20 m-s up a hill inclined at - - sin -1 1-50 to the horizontal when the engine is working at 8-0- 105 W- Find the resistance to motion of the train- g- 9-8 m-s2

The correct option is C 800 NSince, P=Fv F= P/v= 8.0× 10^5/20= 4.0× 10^4N At constant speed, the forces acting on the train are in equilibrium, Resol ...

You visited us 2 times! Enjoying our articles? Unlock Full Access!

Byju's Answer

Standard XII

Physics

Law of Conservation of Mechanical Energy

A train of ma...

Question

A train of mass $2.0 \times 10^{5}$ kg has a constant speed of 20 m/s up a hill inclined at $θ = {sin}^{- 1} (\frac{1}{50})$ to the horizontal when the engine is working at $8.0 \times 10^{5}$ W. Find the resistance to motion of the train. $(g = 9.8 m / s^{2})$

400 N

No worries! We‘ve got your back. Try BYJU‘S free classes today!

800 N

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

1600 N

No worries! We‘ve got your back. Try BYJU‘S free classes today!

1200 N

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is C 800 N
Since, $P = F v$
$F = \frac{P}{v} = \frac{8.0 \times 10^{5}}{20} = 4.0 \times 10^{4} N$
At constant speed, the forces acting on the train are in equilibrium, Resolving the forces parallel to the hill.
$F = R + (2.0 \times 10^{5}) g \times \frac{1}{50}$
$4.0 \times 10^{4} = R + 39200 o r R = 800 N$
Therefore, the resistance is 800 N.

Suggest Corrections

Similar questions

Q. A car of mass

1000

kg is traveling up a hill of 1 in

49

, with the engine working at a constant power of

40 k W

. If the resistance offered to the motion is of

800 N

, then the maximum speed the car attain up the hill is

Q. A bus of mass

1000

kg has an engine which produces a constant power of

50

kW. If the resistance to motion, assumed constant is

1000

N. The maximum speed at which the bus can travel on level road and the acceleration when it is travelling at

25

m/s, will respectively be?

Q. A train of mass M is driven with acceleration 'a' along a straight level track against a constant external resistance R. When the velocity of the train is v, the rate at which the engine of the train is doing work will be

Q. A train has a constant speed of 40 m/s on a level road against resistive force of magnitude

3 \times 10^{4}

N. Find the power of the engine.

Q. A boy sitting at the rear end of a railway compartment of a train, running at a constant acceleration on horizontal rails, throws a ball towards the fore end of the compartment with velocity 20 m/s (relative to train) at an angle

37^{0}

above the horizontal , when the train is running at speed of 10 m/s. If same boy catches the ball without moving from seat and at the same height of projection. Then find the speed of train (in m/s) at the instant of his catching the ball. (Here g = 10

m / s^{2}

;

s i n 37^{0} = 3 / 5

Join BYJU'S Learning Program

A train of mass 2.0×105 kg has a constant speed of 20 m/s up a hill inclined at θ=sin−1(150) to the horizontal when the engine is working at 8.0×105 W. Find the resistance to motion of the train. (g=9.8m/s2)

The correct option is C 800 NSince, P=FvF=Pv=8.0×10520=4.0×104NAt constant speed, the forces acting on the train are in equilibrium, Resolving the forces parallel to the hill.F=R+(2.0×105)g×1504.0×104=R+39200orR=800NTherefore, the resistance is 800 N.

A train of mass $2.0 \times 10^{5}$ kg has a constant speed of 20 m/s up a hill inclined at $θ = {sin}^{- 1} (\frac{1}{50})$ to the horizontal when the engine is working at $8.0 \times 10^{5}$ W. Find the resistance to motion of the train. $(g = 9.8 m / s^{2})$