Answer:
aaaaa
Explanation:
M = Mass of the Earth
m = Mass of satellite
r = Radius of satellite
G = Gravitational constant
The answer is D. Blackbody radiation. The piece of iron glows red because its temperature is around 1000 K, then yellow because its temperature is around 2800 K, and then white because its temperature is around 5500K. This shows that the spectrum of the radiation is determined by absolute temperature, as when the temperature of a blackbody radiator increases, the peak of the radiation curve moves to shorter wavelengths.
Answer:
Explanation:
position of centre of mass of door from surface of water
= 10 + 1.1 / 2
= 10.55 m
Pressure on centre of mass
atmospheric pressure + pressure due to water column
10 ⁵ + hdg
= 10⁵ + 10.55 x 1000 x 9.8
= 2.0339 x 10⁵ Pa
the net force acting on the door (normal to its surface)
= pressure at the centre x area of the door
= .9 x 1.1 x 2.0339 x 10⁵
= 2.01356 x 10⁵ N
pressure centre will be at 10.55 m below the surface.
When the car is filled with air or it is filled with water , in both the cases pressure centre will lie at the centre of the car .
Answer:
v₂ = 2.568 m/s
Explanation:
given,
mass of Corey = 95 Kg
reading of sale for first 3 s when elevator start to move = 850 N
scale reading for the next 3.0 s = 930 N
Gravitation force acting =
F = m g
F = 95 x 9.8
F = 931 N
using newtons second law, due to movement of elevator
F_{net} = m a
W - N = m a₁
931- 850 = 95 x a₁
a₁ = 0.852 m/s²
now,
velocity calculation
v₁ = a₁t
v₁ = 0.852 x 3 = 2.557 m/s
now, For second case
931 - 930 = 95 x a₂
a₂ = 0.011 m/s²
now, velocity after 4 s
v₂ = v₁ + a₂ t
v₂ = 2.557+ 0.011 x (4 - 3)
(4-3) because velocity after 3 second is calculate we need to calculate velocity after 4 s from beginning.
v₂ = 2.557 + 0.011
v₂ = 2.568 m/s
velocity of the elevator is equal to v₂ = 2.568 m/s
Answer: a) 274.34 nm; b) 1.74 eV c) 1.74 V
Explanation: In order to solve this problem we have to consider the energy balance for the photoelectric effect on tungsten:
h*ν = Ek+W ; where h is the Planck constant, ek the kinetic energy of electrons and W the work funcion of the metal catode.
In order to calculate the cutoff wavelength we have to consider that Ek=0
in this case h*ν=W
(h*c)/λ=4.52 eV
λ= (h*c)/4.52 eV
λ= (1240 eV*nm)/(4.52 eV)=274.34 nm
From this h*ν = Ek+W; we can calculate the kinetic energy for a radiation wavelength of 198 nm
then we have
(h*c)/(λ)-W= Ek
Ek=(1240 eV*nm)/(198 nm)-4.52 eV=1.74 eV
Finally, if we want to stop these electrons we have to applied a stop potental equal to 1.74 V . At this potential the photo-current drop to zero. This potential is lower to the catode, so this acts to slow down the ejected electrons from the catode.
