Question:
An electric train is moving with a velocity of 120 km/h. How much distance will it move in 30 s ?
Motion
Q 1.
Derive graphically the equation of motion for position-velocity relation of a body moving with uniform acceleration.
Q 2.
A farmer moves along the boundary of a square field of side 10 m in 40 s. What will be the magnitude of displacement of the farmer at the end of 2 minutes 20 seconds?
Q 3.
Calculate the greatest and the least pressure exerted by a metal block of size 20 cm x 8 cm x 5 cm and having a mass of 5 kg.
Q 4.
A body starts from rest.What is zero ?
Q 5.
In addition to speed,what else should be known to predict the position of a moving body from a given starting point ?
Q 6.
What can you calculate from speed-time graph of a body ?
Q 7.
Why does a person feel pain when he stands on a pile of gravel than when he stands on a bed of sand ?
Q 8.
What is represented by the graphs in Fig.?
.
Q 9.
Relative density of silver is 10.8.The density of water is
.What is the density of silver in SI units ?
Q 10.
What does the path of an object look like when it is in uniform motion?
Q 11.
When will you say a body is in (i) uniform acceleration? (ii) nonuniform acceleration?
Q 12.
Under what conditions(s) is the magnitude of average
Q 13.
What is the relationship between the buoyant force on an object and the liquid displaced by it ?
Q 14.
Air is a fluid and our bodies displace air.As a result of this,a buoyant force is acting on each one of us.
(a)What is the approximate density of your body ?
(b) What is your approximate volume ?
(c) Estimate the magnitude of the buoyant force on you due to the air displaced.Consider your mass to be 75 kg.
(d)Does it mean that your weight is more than the scale reading ?
(Given density of air,pa =
)
Q 15.
An electric train is moving with a velocity of 120 km/h. How much distance will it move in 30 s ?
Q 16.
The speed-time graph for a car is shown is figure below.
(a) Find how far does the car travel in the first 4 seconds. Shade the area on the graph that represents the distance travelled by the car during the period.
(b) Which part of the graph represents uniform motion of the car?
Q 17.
What conclusion do you draw when displacement-time graph of a body is as shown in Fig.?
Q 18.
An object weighs 9.8 N in air and 9.0 N when fully immersed in water.How much is the buoyant force on the object ?
Q 19.
A train 100 m long moving on a straight level track passes a pole in 5 s. Find (a) the speed of the train (b) the time it will take to cross a bridge 500 m long.
Q 20.
A ship is moving at a speed of 56 km/h.One second later,it is moving at 58 km/h.What is its acceleration ?
Q 21.
A farmer moves along the boundary of a square field of side 10 m in 40 s.What will be the magnitude of displacement of the farmer at the end of 2 minutes 20 seconds ?
Q 22.
Can displacement and distance ever be equal ?
Q 23.
What are the values of distance travelled and displacement in covering 10 m from P to Q and coming back ?
Q 24.
The density of turpentine oil is
.What will be its relative density ?
Q 25.
Distinguish between speed and velocity.
Q 26.
Name the quantity that represents rate of change of velocity ?
Q 27.
A weather forecasting plastic balloon of volume
contains hydrogen of density
.The mass of the empty balloon is 7.15 kg.Calcuiate (a) the mass or 'hydrogen in the balloon (b) Tne mass of balloon filled with hydrogen.
Q 28.
What is thrust ?How is it related to pressure ? Give their units.
Q 29.
What is the relation between true weight,apparent weight and the loss in weight of a body immersed in a fluid ? Give some practical applications of Archimedes’Principle.
Q 30.
What does the odometer of an automobile measure?
Q 31.
A train is travelling at a speed of 90 kmh–1. Brakes are applied so as to produce a uniform acceleration of – 0.5 ms–2. Find how far the train will go before it is brought to rest.
Q 32.
What does the slope of distance-time graph indicate?
Q 33.
Fill in the blanks :
The rate of change of velocity of a moving body with time is called ______.
Q 34.
An artificial satellite is moving in a circular orbit of radius 42250 km. Calculate its speed if it takes 24 hours to revolve around the Earth.
Q 35.
Name the terms represented by various symbols in the equation, v = u + at.
Q 36.
What do the graphs shown in Fig.indicate?
Q 37.
Use graphical method to derive the relation
-
= 2 as,where the symbols have their usual meanings.
Q 38.
Write the three equations of uniformly accelerated motion. Give the meaning of each symbol in them.
Q 39.
An object has moved through a distance. Can it have zero displacement? If yes, support your answer with an example.
Q 40.
Under what condition(s) is the magnitude of average velocity of an object equal to its average speed?
Q 41.
A cyclist cycles for t second at a speed of 3 m/s and then for the same time at a speed of 5 m/s along a straight road due north. What is the average speed of the cyclist?
Q 42.
A train is running at a speed of 72 km/h. It crosses a bridge of length half kilometer in 1 minute. Calculate the length of the train.
Q 43.
A scalar quantity has ?
(a) magnitude only
(b) direction only
(c) both direction and magnitude
(d) none of these
Q 44.
What will be the initial velocity of an object under free fall?
Q 45.
Mathematically prove that the distance (S) travelled by an object is the average mean of initial velocity(u) and final velocity(v) having constant acceleration(a) in the direction of motion in a straight line.
Q 46.
What can you say about the motion of an object whose distance-time graph is a straight line parallel to the time axis ?
Q 47.
A particle moves over three quarters of a circle of radius r.What is the magnitude of its displacement ?
Q 48.
Draw speed-time graph for a body (i) at rest (ii) in uniform motion (iii) in uniformly accelerated motion.Discuss the results briefly.
Q 49.
The mass of a solid rectangular block of iron is 23.6 g and its dimensions are 2.1 cm x 1.2 cm x 1.1 cm.Calculate the density of iron.
Q 50.
Why is it easier to swim in sea water than in river water ?
