A new flashlight cell of emf 1.5 volts gives a current of 15 amps, when connected directly to an ammeter of resistance 0.04 Ω. The internal resistance of cell is
(a) 0.04 Ω
(b) 0.06 Ω
(c) 0.10 Ω
(d) 10 Ω
(a) 0.04 Ω
(b) 0.06 Ω
(c) 0.10 Ω
(d) 10 Ω
(b) 0.06 Ω
Five resistances are combined according to the figure. The equivalent resistances between the points X and Y will be
(a) 10 Ω
(b) 22 Ω
(c) 20 Ω
(d) 50 Ω
In meter bridge, the balancing length from left end when standard resistance of 1 Ω is in right gap is found to be 20 cm. The value of unknown resistance is
(a) 0.25 Ω
(b) 0.4 Ω
(c) 0.5 Ω
(d) 4 Ω
A torch bulb rated as 4.5 W, 1.5 V is connected as shown in the figure. The emf of the cell needed to make the bulb glow at full intensity is
(a) 4.5 V
(b) 1.5 V
(c) 2.67 V
(d) 13.5 V
A Daniel cell is balanced on 125 cm length of a potentiometer wire. When the cell is short circuited with a 2 Ω resistance, the balancing length obtained is 100 cm. Internal resistance of the cell will be
(a) 1.5 Ω
(b) 0.5 Ω
(c) 1.25 Ω
(d) 4/5 Ω
A network of resistors is connected to a 16 V battery with internal resistance of 1Ω as shown in the Fig. Compute the equivalent resistance of the network.
(a) 5 ohm
(b) 7 ohm
(c) 9 ohm
(d) 10 ohm
The V-i graph for a conductor at temperature T¹ and T² are as shown in the figure. (T² - T¹) is proportional to
(a) cos θ
(b) sin θ
(c) cot 2θ
(d) tan θ
Plot a graph showing the variation of current I versus resistance R, connected to a cell of emf E and internal resistance r.
The following figure shows the top view of a rod that can slide without friction. The resistance is 5.0Ω and a 2.5 T magnetic field is directed perpendicularly downwards into the paper. Length of the rod is 1.0 m.
In the Young double slit experiment, the fringe pattern as seen on the screen is:
(a) parabola
(b) Hyperbola
(c) Ellipse
(d) Spiral
When tiny circular obstacle is placed in the path of light from a distance source , a bright spot is seen at the centre of the obstacle.
I. It happens due to
II. Polarization of light waves
III. Diffraction of light waves
IV. Interference of light waves
V. Scattering of light waves
A screen is placed 50m from a single slit, which is illuminated with 6000Å light. If the distancebetween the first and third minima in the diffraction pattern is 3.00mm, what is the width of the slit ?
i. 200 µm
ii. 300 µm
iii. 250 µm
iv. 350 µm
In a Young’s double slit experiment the distance between the slit is 1 mm and the distance of screen from the slit is 1 m. If light of wavelength 6000 A is used then the fringe width is:
(a) 0.4 mm
(b) 0.5 mm
(c) 0.6 mm
(d) 0.8 mm
A double slit interference experiment is carried out in air and the entire arrangement is dipped in water. The fringe width
(a) increases
(b) decreases
(c) remains unchanged.
(d) fringe pattern disappears
In a circuit with a coil of resistance 3Ω, the magnetic flux changes from 1.0 Wb to 10.0 Wb in 0.3 s. The charge that flows in the coil during this time is
(a) 2.0 C
(b) 3.0 C
(c) 4.0 C
(d) 1.0 C