This quiz is completed
A body is dropped from the top of a tower and falls freely. The distance covered by it after n seconds is directly proportional to
n2
n
2n−1
2n2−1
in the above question, the distance covered in the nth second is proportional to
n²
n
2n-1
2n² -1
in q. 1 the velocity of the body after n seconds is proportional to
n2
n
2n−1
2n2−1
A ball dropped from a height h reaches the ground in time T. what is its height at time T/2?
h/8
h/4
h/2
3h/4.
The distance time graph of a particle at time t makes an angle 45∘ with the time axis. After one seconds it makes an angle 60∘ with the tie axis. What is the acceleration of the particle.
√3−1
√3+1
√3
1.
A car accelerates from rest at 5 ms−2 and then retards to rest at 3m−2 2.the maximum velocity of the car is 30ms−2 what is the distance covered by the car ?
150 m
240m
300 m
The displacement time graph for the two particles A and B are straight lines inclined at angles 300 and 60∘ with the time axis. The ratio of the velocities VA:VB will be
1:2
1:√3
√3:1
1:3
The velocity 'u' of the body moving along a straight line with constant retardation 'a' reduces by 75% in time t. what is the time taken in doing so ?
u/4a
3u/4a
4u/3a
The acceleration of the particle, starting from rest, varies with time according to the relation: a=−Aω2 sin t.the displacement of this particle at a time t will be
−(1/2)(Aω2sin ωt)t2.
(Ao sin ot).
(Ao cos ot)t.
A sin ot.
A particle is moving eastwards with a velocity of 5 m/s. in 10 seconds the velocity changes to 5 m/s. northwards. The average acceleration in this time is
Zero
1/√2 m/s2. towards north-west.
a car can be stopped over a distance x when its momentum is ' p′. what will be the stopping distance when the momentum is 2p.
x
2x
4x
8x.
The displacement x and time t are related as t=px2+qx+r when p,q,r, are constants. What is the relation between velocity v and the acceleration a?
a∝v
a∝v2
The distance covered by a particle moving on a straight line path at any instant is given by t=ax2+bx. if the instantaneous velocity of the particle be v. What is the acceleration of the particle.
2a v3.
−2a v3.
2a v2.
−2a v2.
A particle moves so that the displacement x at time t is given by x2=1+t2 t2.what is its acceleration.
1 1/x
t2/x3.
A car starts from rest and moves with constant acceleration. The ratio of the distance covered in the nth second to that in n seconds is:
1/2n2−1/n
1/2n2+1/n
2/n−1/n2
2/n+1/n2
The height y and the distance x along the horizontal plane of a projectile on a certain planet are given by y=(8t−10t2) meter and x=6t meter where t is in seconds. the velocity with which the projectile is projected, is:
8 m/s
6 m/s.
10 m/s
not obtained from data
the position (x&y) co-ordinates of particle at the instant t are √21 t and 2t−4t2. respectively. What is the initial speed of the particle
0
3 m/s.
4 m/s.
5 m/s
A shell is fired from a cannon with a velocity V m/s at an angle with the horizontal direction. At the highest point in its path explodes into two pieces of equal mass. one of the pieces retraces its path to the canon then the speed of the other piece immediately after explosion is :
3V cos
2 V cos θ
3/2∨cosθ
√3/2 cos θ.
A train starts from the rest ad acquires with a speed v with uniform acceleration . Then it comes to stop with uniform retardation . What will be the average velocity of the train?
αβ/(α+β)
(α+β)/αβ
v/2
v
A rocket is fired vertically from the ground . it moves upwards with constant acceleration 10ms-2 for 30 seconds after which the fuel is consumed. After what time form the instant o firing the rocket will attain the maximum height ? take g = 10 ms-2.
30 s
45s
60 s
75 s.
The displacement of a particle is given by √x = 2t what is the nature of motion of the particle ?
accelerated
with uniform velocity
retarded
A car accelerates from the rest at constant rate for the first 10 s and covers a distance y in the next 10 s at the same acceleration. Which of the following is true.
x =3y
y =3x
x =y
y = 2x.
A person throws ball into the air one after another at an interval of one second. The next ball is thrown when the velocity of the ball thrown earlier is zero. To what height the ball rise ? take g = 10 ms-2.
5m
10m
A train accelerates from the rest at a constant rate α for some times and then it retards to rest at the constant rate β. If the total distance covered by the particle is x, then what is the maximum velocity of the train .
[{α+β) / 2αβ }x ]1/2.
[{α-β) / 2αβ }x ]1/2.
[{2αβ / (α+β) }x ]1/2.
[{2αβ / (α-β) }x ]1/2.
A train accelerates from rest at a constant rate α for distance x1 and time t1. after that it retards to rest at constant rate β for distance x2 and time t2. which of the following relation is correct?
x1/x2 =α/β = t1/t2.
x1/x2 =β/α = t1/t2.
x1/x2 =α/β = t2/t1.
x1/x2 =β/α = t2/t1.
A ball is dropped from the top of the tower of height h. it covers a distance of h/2 in the last second of its motion How long does the ball remain in air.
√2s
(2+√2) s
2s
(2-√2) s.