Physics-
General
Easy
Question
A square ABCD of side 1mm is kept at distance 15 cm infront of the concave mirror as shown in the figure. The focal length of the mirror is 10 cm. The length of the perimeter of its image will be (nearly):
- 8 mm
- 2 mm
- 12 mm
- 6 mm
The correct answer is: 12 mm
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Two mirrors are inclined at an angle q as shown in the figure. Light ray is incident parallel to one of the mirrors. Light will start retracing its path after third reflection if
Two mirrors are inclined at an angle q as shown in the figure. Light ray is incident parallel to one of the mirrors. Light will start retracing its path after third reflection if
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A steady current 4 A flows in an inductor coil when connected to a 12 V dc source as shown in figure 1. If the same coil is connected to an ac source of 12 V, 50 rad/s, a current of 2.4 A flows in the circuit as shown in figure 2. Now after these observations, a capacitor of capacitance 
is connected in series with the coil and with the same AC source as shown in figure 3 :
The average power supplied to the circuit after connecting capacitance in series is approximately equal to:
A steady current 4 A flows in an inductor coil when connected to a 12 V dc source as shown in figure 1. If the same coil is connected to an ac source of 12 V, 50 rad/s, a current of 2.4 A flows in the circuit as shown in figure 2. Now after these observations, a capacitor of capacitance is connected in series with the coil and with the same AC source as shown in figure 3 :
The average power supplied to the circuit after connecting capacitance in series is approximately equal to:
physics-General
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A steady current 4 A flows in an inductor coil when connected to a 12 V dc source as shown in figure 1. If the same coil is connected to an ac source of 12 V, 50 rad/s, a current of 2.4 A flows in the circuit as shown in figure 2. Now after these observations, a capacitor of capacitance is connected in series with the coil and with the same AC source as shown in figure 3 :
The resistance of the coil is :
A steady current 4 A flows in an inductor coil when connected to a 12 V dc source as shown in figure 1. If the same coil is connected to an ac source of 12 V, 50 rad/s, a current of 2.4 A flows in the circuit as shown in figure 2. Now after these observations, a capacitor of capacitance is connected in series with the coil and with the same AC source as shown in figure 3 :
The resistance of the coil is :
physics-General
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A steady current 4 A flows in an inductor coil when connected to a 12 V dc source as shown in figure 1. If the same coil is connected to an ac source of 12 V, 50 rad/s, a current of 2.4 A flows in the circuit as shown in figure 2. Now after these observations, a capacitor of capacitance is connected in series with the coil and with the same AC source as shown in figure 3 :
The inductance of the coil is nearly equal to
A steady current 4 A flows in an inductor coil when connected to a 12 V dc source as shown in figure 1. If the same coil is connected to an ac source of 12 V, 50 rad/s, a current of 2.4 A flows in the circuit as shown in figure 2. Now after these observations, a capacitor of capacitance is connected in series with the coil and with the same AC source as shown in figure 3 :
The inductance of the coil is nearly equal to
physics-General
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Statement-1 : In a series R,L,C circuit if 
, 
, and 
denote rms voltage across R, L and C respectively and VS is the rms voltage across the source, then 
.
Statement-2 : In AC circuits, kirchoff voltage law is correct at every instant of time.
Statement-1 : In a series R,L,C circuit if , , and denote rms voltage across R, L and C respectively and VS is the rms voltage across the source, then .
Statement-2 : In AC circuits, kirchoff voltage law is correct at every instant of time.
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What is the amount of power delivered by the ac source in the circuit shown (in watts)
What is the amount of power delivered by the ac source in the circuit shown (in watts)
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In the circuit diagram shown, 
. The effective current through the source is:
In the circuit diagram shown, . The effective current through the source is:
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The voltage time (V - t) graph for triangular wave having peak value. 
is as shown in figure The rms value of V in time interval from t = 0 to 
is
The voltage time (V - t) graph for triangular wave having peak value. is as shown in figure The rms value of V in time interval from t = 0 to is
physics-General
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In a black box of unknown elements (L, C or R or any other combination) an AC voltage 
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In a black box of unknown elements (L, C or R or any other combination) an AC voltage is applied and current in the circuit was found to be . Then the unknown elements in the box may be :
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If the readings of 
and 
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is :
If the readings of and are 100 volt each then reading of is :
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In the circuit diagram shown, 
. The effective current through the source is:
In the circuit diagram shown, . The effective current through the source is:
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A current source sends a current 
. When connected across an unknown load gives a voltage output of, 
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When an AC source of emf 
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When an AC source of emf is connected across a circuit, the phase difference between the E and the current i in the circuit is observed to be , as shown in the diagram. If the circuit consists possibly only of R-C or R-L or L-C series, find the relationship between the two elements.
physics-General
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Statement-1 : A spherical surface of radius of curvature R separates two media of refractive index n1 and n2 as shown. If an object O (a thin small rod) is placed upright on principal axis at a distance R from pole (i.e., placed at centre of curvature), then the size of image is same as size of object.
Statement-2 : If a point object is placed at centre of curvature of spherical surface separating two media of different refractive index, then the image is also formed at centre of curvature, i.e., image distance is equal to object distance.
Statement-1 : A spherical surface of radius of curvature R separates two media of refractive index n1 and n2 as shown. If an object O (a thin small rod) is placed upright on principal axis at a distance R from pole (i.e., placed at centre of curvature), then the size of image is same as size of object.
Statement-2 : If a point object is placed at centre of curvature of spherical surface separating two media of different refractive index, then the image is also formed at centre of curvature, i.e., image distance is equal to object distance.
physics-General
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Statement-1 : A ray is incident from outside on a glass sphere surrounded by air as shown. This ray may suffer total internal reflection at second interface.
Statement 2 : For a ray going from denser to rarer medium, the ray may suffer total internal reflection.
Statement-1 : A ray is incident from outside on a glass sphere surrounded by air as shown. This ray may suffer total internal reflection at second interface.
Statement 2 : For a ray going from denser to rarer medium, the ray may suffer total internal reflection.
physics-General
