Study this electrical circuit. It consists of a powerful battery, a bulb, an electromagnet and a movable connection. The connection is designed in such a way that it closes (that is, it allows electric current to pass) when the electromagnet is not magnetised; but opens when the electromagnet is magnetised. If the electromagnet takes 5 seconds to get magnetised, what will be status of the electric bulb?
Important Questions on Electric Current and Its Effects
See the circuit shown below in figure P. If the battery is connected the other way (as shown in figure Q), what will happen?
The diagram shows a flashlight battery and a bulb connected by wires to various substances. Which of the bulbs will light?
Many electrical devices like televisions and electric irons have plugs which have 3 pins. However, other devices sometimes work with only 2 pins. Why is the third pin necessary?
When connected as shown, the bulb glows, but dimly. Which of these CAN be the explanation for this:
Instead of a soft iron core, if we wind a current-carrying wire around a wooden pencil, would it still deflect a magnetic compass needle?
The following diagram shows four circuits A, B, C and D. Each circuit has a cell and a torch bulb. Name the circuits in which the bulb will glow? Give reason to your answer
State whether the statement is true or false. Correct it if the statement is false.
In an electric bell, the hammer strikes the gong because the gong is magnetic.
