A photon is absorbed
your question is incomplete, please consider revising it.
Answer:
E) a billion times brighter
Explanation:
- <u>The sun is a star, which is about billion times brighter as the reflected light from any planet orbiting around it. </u>
- The brightness is based on its composition and its position from the planet. The sun happens to be the brightest star on the Earth's sky which is about 13 billion times brighter than the next brightest star.
Given:
Shaft Power, P = 7.46 kW = 7460 W
Speed, N = 1200 rpm
Shearing stress of shaft,
= 30 MPa
Shearing stress of key,
= 240 MPa
width of key, w = 
d is shaft diameter
Solution:
Torque, T = 
where,

= 59.365 N-m
Now,


d = 0.0216 m
Now,
w =
=
= 5.4 mm
Now, for shear stress in key
= 
we know that
T =
= F. 
⇒
= 
⇒
= 
length of the rectangular key, l = 4.078 mm
Explanation:
While studying the velocity of a cheetah over time in a spreadsheet program is given by :
y = 2.2 x + 1.2 ...(1)
We know that,
v=v₀+at ...(2)
v₀ is velocity when t = 0, v is velocity after time t, a is acceleration and t is time.
If we consider time t on x-axis and v on y axis, then only we can draw a plot of equation (2). On comparing equation (1) and (2) we get :
a = 2.2 (but it is not correct as we don't know about axes).
Hence, the correct option is (a) "We cant tell without knowing what was plotted on the horizontal and vertical axes"
Answer:
a) 37.70 m/s
b)710.6 m/s²
Explanation:
Given that ;
Mass of object = 2 kg
Radius of the motion = 2m
Frequency of motion = 3 rev/s
The formula to apply is;
v= 2πrf where v is linear speed
v = 2×π×2×3 =12π = 37.70 m/s
Centripetal acceleration is given as;
a= 4×π²×r×f²
a= 4×π²×2×3²
a=710.6 m/s²