A heater coil is cut into two equal parts and only one part is now used in the heater. The heat generated will now be
doubled
four times
one fourth
halved
Additional Questions
|
Two cities are 150 km apart. Electric power is sent from one city to another city through copper wires. The fall of potential per km is 8 volt and the average resistance per km is 0.5 Ω. The power loss in the wire is |
Answer |
|
The thermistors are usually made of: |
Answer |
|
A potentiometer circuit has been set up for finding the internal resistance of a given cell. The main battery, used across the potentiometer wire, has an emf of 2.0 V and a negligible internal resistance. The potentiometer wire itself is 4 m long. When the resistance, R, connected across the given cell, has values of |
Answer |
|
In a potentiometer experiment, the balancing length with a cell is 240 cm. On shunting the cell with a resistance of 2 Ω, the balancing length becomes 120 cm. The internal resistance of the cell is |
Answer |
|
The thermo emf of a thermocouple varies with the temperature θ of the hot junction as E = aθ + bq2 (in volts) where the ratio a/b is 700°C. If the cold junction is kept at 0°C, then the neutral temperature of the thermocouple is: |
Answer |
|
The supply voltage to a room is 120 V. The resistance of the lead wires is 6 Ω. A 60 W bulb is already switched on. What is the decrease of voltage across the bulb, when a 240 W heater is switched on in parallel to the bulb? |
Answer |
|
Two large vertical and parallel metal plates having a separation of 1 cm are connected to a DC voltage source of potential difference X. A proton is released at rest midway between the two plates. It is found to move at 45° to the vertical JUST after release. Then X is nearly |
Answer |
|
Two heating coils of resistances 10 Ω and 20 Ω are connected in parallel and connected to a battery of emf 10 V and internal resistance 1 Ω. The power consumed by them are in the ratio |
Answer |
|
In an LCR circuit as shown below both switches are open initially. Now switch S1 is closed, S2 kept open (q is charge on the capacitor and τ = RC is Capacitive time constant). Which of the following statement is correct? |
Answer |
|
Three resistances 2 Ω, 3 Ω and 4 Ω are connected in parallel. The ratio of currents passing through them when a potential difference is applied across its ends will be |
Answer |
