Kinetic energy = 1/2 m v^2 = 1/2 x1.5 x10^-3 x 0.36
C. Gamma rays have more energy than infrared rays
Answer:
m = 0.4 [kg]
Explanation:
Weight is considered as a force and this is equal to the product of mass by gravitational acceleration.

where:
W = weight = 0.8 [N]
m = mass [kg]
g = gravity acceleration 2[N/kg]
Therefore:
![m=W/g\\m = .8/2\\m = 0.4 [kg]](https://tex.z-dn.net/?f=m%3DW%2Fg%5C%5Cm%20%3D%20.8%2F2%5C%5Cm%20%3D%200.4%20%5Bkg%5D)
Answer:
Explanation:
velocity of sound in air at 20⁰C is 343 m /s
velocity of sound in water at 20⁰C is 1481 m /s
The wavelength of the sound is 2.86 m in the air so its frequency
= 343 / 2.86 = 119.93 .
This frequency of 119.93 will remain unchanged in water .
wavelength in water = velocity in water / frequency
= 1481 / 119.93
= 12. 35 m .
Answer:
<em>The kinetic energy of a spinning disk will be reduced to a tenth of its initial kinetic energy if its moment of inertia is made five times larger, but its angular speed is made five times smaller.</em>
<em></em>
Explanation:
Let us first consider the initial characteristics of the angular motion of the disk
moment of inertia = 
angular speed = ω
For the second case, we consider the characteristics to now be
moment of inertia =
(five times larger)
angular speed = ω/5 (five times smaller)
Recall that the kinetic energy of a spinning body is given as

therefore,
for the first case, the K.E. is given as

and for the second case, the K.E. is given as


<em>this is one-tenth the kinetic energy before its spinning characteristics were changed.</em>
<em>This implies that the kinetic energy of the spinning disk will be reduced to a tenth of its initial kinetic energy if its moment of inertia is made five times larger, but its angular speed is made five times smaller.</em>