physics practice test

2
Q.1 If v = A t +Bt 2 + Ct 3 where v is velocity, t is time A, B and C are constant then the dimensional formula of B is : (a) [ M 0 LT 0 ] (b) [ ML 0 T 0 ] (c) [ M 0 L 0 T 0 ] (d) [ M 0 LT -3 ] Q.2 Taking density (p), velocity (v) and area (a) to be fundamental unit the dimensions of force are: (a) [av 2 p] (b) [a 2 vp] (c) [avp 2 ] (d) [a 0 vp] Q.3 If x = a sin θ+b cos θ a+b , then : (a) the dimensions of x and a are same (b) the dimensions of a and b are not same (c) x is dimensionless (d) none of the above Q.4 If A = B + C D +E the dimensions of ‘B’ and ‘C’ and [L T -1 ] and [M 0 L T 0 ], respectively. Find the dimensions of A, D and E: (a) A = [M 0 L 0 T -1 ], D = [T ] , E = [LT] (b) A = [M LT 0 ], D = [T 2 ] , E = [T 2 ] (c) A = [LT -1 ], D = [MT ], E = [MT] (d) A = [L T -1 ], D = [T ] , E = [T] Q.5 The changes in a, function y and the independent variable x are related as dy dx = x 2 . Find y as a function of x. Q6. The electric current in a charging R - C circuit is given by i = i 0 e -t/RC where i 0 , R and C are constant parameters of the circuit and t is time, then rate of change of current at t = 10 RC. Q7. The momentum p of a particle changes with time t according to the relation dp dt = (1O N) + (2 N/s)t. If the momentum is zero at t =0, what will the momentum be at t =10 s ?

Upload: at-tanwi

Post on 26-Sep-2015

1 views

Category:

Documents


0 download

DESCRIPTION

physics questions

TRANSCRIPT

Q.1 If where v is velocity, t is time A, B and C are constant then the dimensional formula of B is :

(a) [ M0 LT0](b) [ ML0 T0](c) [ M0 L0 T0] (d) [ M0 LT-3]

Q.2 Taking density (p), velocity (v) and area (a) to be fundamental unit the dimensions of force are:

(a) [av2p] (b) [a2vp](c) [avp2] (d) [a0vp]

Q.3 If x = , then :

(a) the dimensions of x and a are same(b) the dimensions of a and b are not same

(c) x is dimensionless(d) none of the above

Q.4 If A = B + the dimensions of B and C and [L T-1] and [M0 L T0], respectively. Find the dimensions of A, D and E:

(a) A = [M0 L0 T-1], D = [T ] , E = [LT](b) A = [M LT0], D = [T2 ] , E = [T2]

(c) A = [LT-1], D = [MT ], E = [MT](d) A = [L T-1], D = [T ] , E = [T]

Q.5 The changes in a, function y and the independent variable x are related as = x2. Find y as a function of x.

Q6. The electric current in a charging R - C circuit is given by i = i0e-t/RC where i0, R and C are constant parameters of the circuit and t is time, then rate of change of current at

t = 10 RC.

Q7. The momentum p of a particle changes with time t according to the relation = (1O N) + (2 N/s)t. If the momentum is zero at t =0, what will the momentum be at t =10 s ?

Q8.If displacement is given by x = t3 -12t+4.Find the time when x is

(i)maximum (ii)minimum

Q9.In above question find the acceleration at t=2s.

Q10. The velocity of a particle is given by v= t2 t + 1 where t is time. Then find the acceleration and displacement at t=2s, if displacement at t=0 is 5m.

dx

dy

dt

dp

3

2

Ct

Bt

t

A

v

+

+

=

b

a

b

a

+

+

q

q

cos

sin

E

D

C

+