Given
Weight of the block A, Wa = 20 lb, weight of block B Wb = 50 lb. Applied
force to block A, P = 6lb, coefficient of static friction µs = 0.4, coefficient
of kinetic friction µk = 0.3. If a force P
is applied to the body, no relative motion will take place until the applied
force is equal to the force of friction Ff, which is acting opposite to the
direction of motion. Magnitude of static force of friction between block A and
block B, Fs = µsN, where N is
reaction force acting on block A. Now, resolve the forces Fx = max. P = (mA +
mB)a,
6 = (20 / 32.2 + 50 / 32.2)a
2.173a = 6
A = 2.76 ft/s^2
To check slipping occurs between block A and block B, consider block A:
P – Ff = mAaA
6 – Ff = 1.71
Ff = 4.29 lb
And also,
N = wA. We know static friction,
Fs = µsN
Fs = 0.4 x 20
Fs = 8lb
Frictional force is less than static friction. Ff < Fs
<span>Therefors, acceleration of block A, aA = 2.76 ft/s^2, acceleration of
block B aB = 2.76 ft/s^2</span>
Answer:
f=8.219*10^{8}Hz
Explanation:
We are going to use the formula v=fλ
Where v= velocity of radio waves
f= frequency
λ= wavelength of wave
- radio waves are electromagnetic waves and as such they have the speed of light which is 3*10^{8}m/s.
- also when a wave travels from one medium to another, the wavelength changes while the frequency remains the same.
- calculating for the frequency of the wave in air also gives us the frequency in the window glass.
f=\frac{v}{λ}
v=3*10^{8}m/s.
λ=36.5 cm = 36.5/100= 0.365m
f=\frac{3*10^{8}m/s.}{0.365m}
f=8.219*10^{8}Hz
Answer:
By electromagnetic waves.
Explanation:
The sun transfers heat to earth via electromagnetic waves in twomajor ways:
this is the transfer of energy by invisible electromagnetic ways.
The radiant sun energy warms the atmosphere and becomes heat energy. This transfer of heat through movement of fluids or usually air is called convection.
The heat released by the water when it cools down by a temperature difference

is

where
m=432 g is the mass of the water

is the specific heat capacity of water

is the decrease of temperature of the water
Plugging the numbers into the equation, we find

and this is the amount of heat released by the water.
They are both right because you can note both things, I mean Raphael and Lucinda, both has a right statement or explanation about the wave. Wave by nothing is both for its wavelength and for its frequency. So Raphael and Lucinda are both correct because you can note both wavelength and frequency.