Answer:
a ) 2.68 m / s
b ) 1.47 m
Explanation:
The jumper will go down with acceleration as long as net force on it becomes zero . Net force of (mg - kx ) will act on it where kx is the restoring force acting in upward direction.
At the time of equilibrium
mg - kx = 0
x = mg / k
= (60 x 9.8 ) / 800
= 0.735 m
At this moment , let its velocity be equal to V
Applying conservation of energy
kinetic energy of jumper + elastic energy of cord = loss of potential energy of the jumper
1/2 m V² + 1/2 k x² = mg x
.5 x 60 x V² + .5 x 800 x .735 x .735 = 60 x 9.8 x .735
30 V² + 216.09 = 432.18
V = 2.68 m / s
b ) At lowest point , kinetic energy is zero and loss of potential energy will be equal to stored elastic energy.
1/2 k x² = mgx
x = 2 m g / k
= (2 x 60 x 9.8) / 800
= 1.47 m
Answer: 225 V
Explanation:
<u>Given:</u>
Secondary voltage,V2 = 150v
Resistance is connected across secondary winding,∴R2 = 20Ω
Supply current, ie, I1 = 5A
Voltage is potential energy per coulomb (J/C). So use the voltage and charge on an electron to get E=V•Q=1.5e8•1.602e-19=2.4e-11J
Your answer:
150 kilometer's per hour.
I think the answer should be D.<span>It reduces the amount of thermal energy that is transferred from outside to inside the container. </span>