Page 124 - Ripples SCIENCE 7 - TEJPUR Edition 2024 Answer Key
P. 124

4.   Which of the following is not an effect of electric current?

                      (a) Heating effect     (b) Chemical effect   (c) Magnetic effect   (d) Light effect

                Ans:  (d)
                  5.   Which of the following is an insulator?

                       (a) Mercury           (b) Glass             (c) Copper             (d) Silver

                Ans:   (b)
                  6.   The full form of MCB is …………………… .

                      (a) Magnetic circuit breaker                 (b) Miniature circuit breaker

                      (c) Magnetic circuit box                     (d) Miniature circuit box
                Ans:  (b)

                  7.   An …………………… is a safety device to prevent damage to an electric circuit when

                       excessive current flows through it.

                      (a) Battery            (b) Resistance        (c) Electric fuse      (d) Electromagnet
                Ans:   (c)

                  8.   The filament of the bulb is made of …………………… as it has high melting point.

                      (a) Tungsten           (b) Copper            (c) Gold               (d) Lead
                Ans:  (a)

          B.   Fill in the blanks.

                  1.   Our body is a ...................... of electricity.
                Ans:  conductor

                  2.   The combination of two or more cells is called a ...................... .

                Ans:  battery

                  3.   The safety device based on the heating effect of electric current is called ................. .
                Ans:  electric fuse

                  4.   Electric current is a flow of ...................... .

                Ans:  electric charge
                  5.   Water heaters have a ...................... that gets hot when current passes through it.

                Ans:   heating element

                  6.   It is  mandatory for various  electrical  products,  such  as  electrical  wires, switches,
                       electric motors, heaters and kitchen appliances, to carry the ...................... mark.

                Ans:  ISI

                  7.   ...................... is a device based on magnetic effect of electric current.
                Ans:  Electromagnet



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