Answer: 3P/2
Explanation: Let the resistance of the bulbs be R.
now lets consider a Voltage V is supplied to the parallel circuit such that
V=IR
both single bulb( bulb 3) and the two bulbs ( bulb 1 and bulb 2) are provided the same Voltage
( as the voltage remains same in parallel circuit)
we can calculate the Current across both circuits
At Bulb 3
Current 1=V/R
Power1=Voltage * Current1
Power1=V*V/R
Power1=P
At Bulb 1 and Bulb 2
Total Resistance= R+R=2R
Power2=Voltage * Current2
Answer:
Explanation:
Potential energy =
Answer:
(a) 89 m/s
(b) 11000 N
Explanation:
Note that answers are given to 2 significant figures which is what we have in the values in the question.
(a) Speed is given by the ratio of distance to time. In the question, the time given was the time it took the pulse to travel the length of the cable twice. Thus, the distance travelled is twice the length of the cable.
(b) The tension, , is given by
where is the speed,
is the tension and
is the mass per unit length.
Hence,
To determine , we need to know the mass of the cable. We use the density formula:
where is the mass and
is the volume.
If the length is denoted by , then
The density of steel = 8050 kg/m3
The cable is approximately a cylinder with diameter 1.5 cm and length or height of 620 m. Its volume is
