Half-life, in radioactivity, the interval of time required for one-half of the atomic nuclei of a radioactive sample to decay (change spontaneously into other nuclear species by emitting particles and energy), or, equivalently, the time interval required for the number of disintegrations per second of a radioactive
The first thing you should know is that the work is defined as:
W = F * d
Where
F = force
d = displacement
We have then
(a) the block
F = (0.2) * (100) = 20
d = 100
W = (20) * (100) = 2000 ft.lbf
(b) the man as the system.
F = (0.2) * (100 + 180) = 56
d = 100
W = (56) * (100) = 5600 ft.lbf
answer:
(a) 2000 ft.lbf
(b) 5600 ft.lbf
M= gpe / gh
G= gpe / mh
H=gpe / mg
Answer:
4.5
Explanation:
volume is length x breath x height
since 75 is in cm, we convert it to metre
= 0.75m
= 1.2m x 5m x 0.75m
=
Answer:
shift the wavelength of spectral lines
Explanation:
The Doppler effect is commonly used in the field of astronomy to study the motion of astronomical objects such as a star, planets, and distant galaxies. This results in the changing of wavelength and shifting of the spectral lines, due to the relative and continuous motion of the receiver and the source. This is known as the red-shifting, where the lights in the spectrum move towards the highest wavelength, i.e towards the red light. This Doppler effect signifies that the distance between the distant galaxies and earth increases with the increasing recessional velocity.