Physics Test 111

Result

Physics Test 111

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
4 / -1

A projectile is fired with velocity v₀ from horizontal surface making an angle θ with vertical. If the wind imparts constant horizontal acceleration 'a' to the left then at what angle 'θ' projectile must be fired so that is returns to the point of projection ? (Assume 'g' to be uniform)

A
θ = tan^-1(a / 2g)

B
θ = tan^-1(2a² / g²)

C
θ = tan^-1(a / g)

D
θ = tan^-1(g / a)

Solution
Question 2
4 / -1

A stone is tied to a string of length ℓ and is whirled in a vertical circle with the other end of the string as the centre. At a certain instant of time the stone is at its lowest position and has speed 'u'. The magnitude of the change in velocity as it reaches a position where the string is horizontal (g being acceleration due to gravity) is :

A

B

C

D

Solution
Question 3
4 / -1

Find the velocity of block on reaching ground if released from rest as shown.

A
v = 10 √2 m/s

B
v = 12 √2 m/s

C
v = 15 √2 m/s

D
None of these
Question 4
4 / -1

Blocks of mass M₁ and M₂ are connected by a cord which passes over the pulleys P₁ and P₂ as shown in the figure. If there is no friction, the acceleration of the block of mass M₁ will be :

A
M₂g / (4M₁ + M₂)

B
2M₂g / (4M₁ + M₂)

C
2M₁g / (M₁ + 4M₂)

D
2M₁g / (M₁ + M₂)

Solution

M₁a₁ = T, M₂g – 2T = M₂a₂ , a₁ = 2a₂

Hence M₁(2a₂) = T and M₂g – 2M₁(2a₂) = M₂a₂

M₂g = a₂ (4M₁ + M₂) so a₂ = M₂g / 4M₁ + M₂
Question 5
4 / -1

Calculate the hinge force when the rod of mass M becomes vertical. Initial situation is shown in figure and string is then cut. (hinge is frictionless)

A
F_x = 0; Fy = 3/2 Mg

B
F_x = Mg; F_y = 5/2 Mg

C
F_x = 3/2Mg; F_y= 3/2 Mg

D
F_x = 0 ; F_y= 5/2 Mg

Solution
Question 6
4 / -1

A weight W rests on the bar AB as shown in figure. The cable connecting W & B passes over frictionless pulley. If bar AB has negligible weight, find reaction at A for system to be in equilibrium.

A
W (L-a) / (L + a)

B
W (L+a) / (L - a)

C
W (L+2a) / (L + a)

D
W (L-2a) / (L + a)

Solution
Question 7
4 / -1

Find the maximum height upto which disc can reach on the incline plane when given velocity v horizontally & disc is performing pure rolling motion.

A
h_max = 3v² / 4g

B
h_max = 2v² / g

C
h_max = 4v² / 3g

D
h_max = v² / g

Solution
Question 8
4 / -1

The electric field of a plane electromagnetic wave in vaccum is represented by with C = 3 × 10⁸ m/sec E_z = 0 & all quantities are is S.I. units. Find the component of magnetic field associated with the wave :

A
0.15 × 10^-8 cos

B
0.17 × 10^-8 cos

C
0.17 × 10^-8 sin

D
0.15 × 10^-8 sin

Solution

The wave propogate in x-direction while electric field oscillates in y-direction. Thus the electric field resides in the x-y plane. Since the magnetic field is perpendicular to both E & propogation direction, it must be in x-z plane ∴ B_x = 0, B_y = 0, B_z ≠ 0 and
Question 9
4 / -1

A wave is given by the equation y = 10 sin 2π (100 t – .02x) + 10 sin 2π (100 t + .02x). The loop length of the stationary wave produced will be :

A
25 units

B
30 units

C
35 units

D
none of these

Solution
Question 10
4 / -1

When an object is at distance x and y from a lens, a real image and a virtual image is formed respectively having same magnification. The focal length of the lens is

A
x+y / 2

B
x-y

C
√xy

D
x + y

Solution