Question

pleas ans. this question 4​

Answer 1

Answer == 】

For question 1

When the wire is doubled the length = 1/2 and area == 2A or twice

we know R = PL/A.......(1)

for second case when R1 is new resistance.=

R1 = P(L/2) / 2A .........(2)

eq. (1) ÷ eq (2)

So R1/R = {P(L/2) / 2A} / {PL/A}

When we solve this we get

R1/R = 4=> R1 = R/4 = 4/4 = 1OHM

For 2nd question

◆For T.V set

Power(P) = 250w,

Time (t) => 1hr =60x60=3600

For toaster power=1200W, time =10min = 10*60 =600s

we know E=P*T

Energy consumed by the TVset = 250*3600 =9*105J

Energy consumed by a toaster = 1200 x 600 = 7.2*105J

Energy consumed by a 250 W TV set in 1h is more than the energy consumed by a toaster of power 1200 W in 10 minutes.

HOPE IT WILL HELP YOU