Answer: 1.95s
Explanation:
Given
ma = 290 cos 34.9 - fk
fk = 290 cos 34.9 - ma
fn = mg + 400 sin Φ
fn = 290 + 400 sin 34.9
fn = 290 + 228.9
fn = 518.9
fk = fn * uk
uk = 0.57
290 cos 34.9 - ma = 518.9 * 0.57
290 cos 34.9 - ma = 295.8
290 cos 34.9 - 295.8 = ma
ma = -58
m = 290/10 = 29
a = 58/29
a = 2
Using equation of motion
S = ut + .5at²
3.8 = 0 + .5*2*t²
3.8 = t²
t = 1.95s
Answer:
Option A
Measures light from distant objects
Explanation:
A spectroscope is used to measure the use of light from a distant object to work out the object is made of.
It could be the single-most powerful tool astronomers use.
Professor Fred Watson from the Australian Astronomical Observatory says that "It lets you see the chemicals being absorbed or emitted by the light source"
Your question seems incomplete, however, I might help you solve the problem even though the values are not given. The intensity of a traveling plane electromagnetic wave can be computed using the following equation:
S = (c/u0) * B^2
where s is the EM wave intesity
c is the speed of light
B is the magnetic field
u0 is the energy density
Answer: v= 160ft/s
a=32ft/s^2 constant
Explanation:
s(t)=400-16t^2 derivative of position is velocity v(t) and derivative of velocity is acceleration a(t) so let s(t)=0 to find the time of flight to reach the ground and take the two derivatives and use the time found and solve. Also acceleration is a constant as it’s gravity.
0=400-16t^2
400=16t^2
25=t^2
t=5s
ds/dt=v(t)=0-32t
dv/dt=a(t)=-32 constant(gravity)
v(t)=-32(5s)= -160ft/s negative sign is only showing direction
Intensity:
Decibels
Amplitude:
Meters
Frequency: Hertz
<u>Explanation:</u>
The Wave is not visible to eyes and they can easily propagate through vacuum. the average power travelling at a given period of time in a space is the intensity. Decibels is the measure of intensity. it is measured in the decibel scale. The wave's strength and the intensity gives the amplitude of wave. It is measured using meters.
The wave's amplitude and the energy has a direct proportionality. The number occurrence of wave cycles per second refers to the frequency of wave. it is measured in hertz. it is also measured as the number of cycles that occurs per second.