Question

1. A body is moving with a velocity of 12m/s and it comes to rest in 18m, what was the acceleration? 2.A body starts from rest and moves with a uniform acceleration of 4m/s until it travels a distance of 800m, find the find velocity? 3.The driver of a car traveling along a straight roadwith a speed of 72KM ph observes a signboard which gives the speed limit to be 54KM ph. The signboard is 70m ahead when the driver applies the brakes0calculate the acceleration of the car which will cause the car to pass the signboard at the stated speed limit? 4.Differentiate between scalars and vectors? 5. Draw the graph for uniform retardation – (a) position – time graph (b) velocity – time (c) Acceleration- time 6. A bullet travelling at 360 m/s; strikes a block of soft wood. The mass of the bullet is 2.0g. The bullet comes to rest after penetrating10cm into the wood? a) Find the average deceleration force exerted by the wood. b) Find the time taken by the bullet to come to rest. 7. A body of mass 10Kg starts from rest and rolls downan inclined plane. Itrolls down 10m in 2S? a) What is the acceleration attained by the body. b) What is the velocity of the body at 2S? c) What is the force acting on the body? 8. Two objects A and B are dropped from a height the object B being dropped. S after A was dropped. How long after A was dropped will A and B be 10m apart? 9. The radius of earth is 6370Km and of mars is 3400 Km. If an object weighs 200N or earth, what will be its weight on mars. The massof mars is 0.11 that of earth. 10. A stone is dropped from a height of 50m on earth. At the same time, another stone is thrown vertically upwards from the ground with avelocity up wards from the ground with a velocity of 50m/s. At what height from the ground will the two stones meet (g = -10 m/s 2 )

Answer 1

1. u = 12m/s
s=18m
v=0m/s
a=?
using 3rd equation of motion,
V2= U2+2as
(0)2= (12)2+2×a×18
0= 144+36a
36a= - 144
a = - 4 m/S2 ( ans)

2. u= 0
v= ?
a= 4m/S2
s= 800 m
using 3rd equation of motion,
V2= U2+2as
V2 = (0)2+2×4×800
V2 = 6400
v = 80 m/s

4. scalars -
the quantities having only magnitude not direction.
eg. mass, length,time etc.

vectors-
those quantities having both magnitude as well as direction.
eg. velocity,force,torque etc.

later, I will tell you remaining questions....

Answer 2

Answer:1. u = 12m/s

s=18m

v=0m/s

a=?

using 3rd equation of motion,

V2= U2+2as

(0)2= (12)2+2×a×18

0= 144+36a

36a= - 144

a = - 4 m/S2 ( ans)

2. u= 0

v= ?

a= 4m/S2

s= 800 m

using 3rd equation of motion,

V2= U2+2as

V2 = (0)2+2×4×800

V2 = 6400

v = 80 m/s

4. scalars -

the quantities having only magnitude not direction.

eg. mass, length,time etc.

vectors-

those quantities having both magnitude as well as direction.

eg. velocity,force,torque etc.

later, I will tell you remaining questions....