Answer:
The human retina can only detect incident light that falls in waves 400 to 720 nanometers long, so we can't see microwave or ultraviolet wavelengths. This also applies to infrared lights which has wavelengths longer than visible and shorter than microwaves, thus being invisible to the human eye.
Pressing (Win+L) will quickly lock a laptop
Answer:
a)
, b)
, c) D. The magnitud of the change in the ball's momentum.
Explanation:
a) The magnitude of the change in the ball's momentum is:
![\Delta p = (0.275\,kg)\cdot \left[\left(1.63\,\frac{m}{s} \right)-\left(-3.28\,\frac{m}{s} \right)\right]](https://tex.z-dn.net/?f=%5CDelta%20p%20%3D%20%280.275%5C%2Ckg%29%5Ccdot%20%5Cleft%5B%5Cleft%281.63%5C%2C%5Cfrac%7Bm%7D%7Bs%7D%20%5Cright%29-%5Cleft%28-3.28%5C%2C%5Cfrac%7Bm%7D%7Bs%7D%20%5Cright%29%5Cright%5D)

b) The change in the magnitude of the ball's momentum:
![\Delta p' = (0.275\,kg)\cdot \left[(1.63\,\frac{m}{s} )-(3.28\,\frac{m}{s} ) \right]](https://tex.z-dn.net/?f=%5CDelta%20p%27%20%3D%20%280.275%5C%2Ckg%29%5Ccdot%20%5Cleft%5B%281.63%5C%2C%5Cfrac%7Bm%7D%7Bs%7D%20%29-%283.28%5C%2C%5Cfrac%7Bm%7D%7Bs%7D%20%29%20%5Cright%5D)

c) The magnitude of the change in the ball's momentum is more directly related to the net force acting on the ball, as it measures the effect of the force on change in ball's motion at measured time according to the Impact Theorem. So, the right answer is option D.
Answer
Given,
Energy absorbed, 
Energy expels,
Temperature of cold reservoir, T = 27°C
a) Efficiency of engine



b) Work done by the engine



c) Power output
t = 0.296 s



Answer:
Acceleration of that planet is 30
.
Given:
initial speed of hammer = 0 
time = 1 s
distance = 15 m
To find:
Acceleration due to gravity = ?
Formula used:
Distance covered by hammer is given by,
s = ut + 
s = distance
u = initial speed of hammer
t = time taken by hammer to reach ground
a = acceleration
Solution:
Distance covered by hammer is given by,
s = ut + 
s = distance
u = initial speed of hammer
t = time taken by hammer to reach ground
a = acceleration
u = 0
t = 1 s
s = 15 m
a = g
Thus substituting these value in above equation.
15 = 0 + 
g = 15 × 2
g = 30 
Thus, acceleration of that planet is 30
.