Answer:
The magnitude of the field is 8.384×10^-4 T.
Explanation:
Now, i start solving this question:
First, convert the potential difference(V) 2 kv to 2000 v.
As, we have the final formula is qvB = mv^2/r. It came from the centripetal force and the magnetic force and we know that these two forces are equal. When dealing with centripetal motion use the radius and not the diameter so
r = 0.36/2 = 0.18 m.
As, we are dealing with an electron so we know its mass is 9.11*10^-31 kg and its charge (q) is 1.6*10^-18 C.
We can solve for its electric potential energy by using ΔU = qV and we know potential energy initial is equal to kinetic energy final so ΔU = ΔKE and kinetic energy is equal to 1/2mv^2 J.
qV = 1/2mv^2
(1.6*10^-19C)(2000V) = (1/2)(9.11*10^-31kg) v^2
v = 2.65×10^7 m/s.
These all above steps we have done only for velocity(v) because in the final formula we have 'v' in it. So, now we substitute the all values in that formula and will find out the magnitude of the field:
qvB = mv^2/r
qB = mv/r
B = mv/qr
B = (9.11*10^-31 kg)(2.65×10^7 m/s) / (1.6*10^-19 C)(0.18 m)
Hence, B = 8.384*10^-4 T.
Answer: the water level would rise since the pebble displaces minimal water compared to the boat.
Explanation:..........
F = 130 revs/min = 130/60 revs/s = 13/6 revs/s
t = 31s
wi = 2πf = 2π × 13/6 = 13π/3 rads/s
wf = 0 rads/s = wi + at
a = -wi/t = -13π/3 × 1/31 = -13π/93 rads/s²
wf² - wi² = 2a∅
-169π²/9 rads²/s² = 2 × -13π/93 rads/s² × ∅
∅ = 1209π/18 rads
n = ∅/2π = (1209π/18)/(2π) = 1209/36 ≈ 33.5833 revolutions.
Answer:
None of the stars give of light that is red-shifted
Explanation:
Motion of the observer or the source will cause a change in the wavelength of a wave. This is known as the Doppler effect. When an object and observer are getting close, blue shift occurs i.e., the wavelength gets shorter. When an object and observer are getting farther red shift occurs i.e., the wavelength gets longer.
Here, both the stars are getting closer to us so blue shift will occur.
Answer:
3.085 [m].
Explanation:
1) The rule:
m₁*g*l₁=m₂*g*l₂, where m₁ and l₁ - the mass and distance for the small child, m₂ and l₂ - for the big child;
2) according to the condigion l₁+l₂=5, then
3) it is possible to make up the system:

4) finally, l₁=145/47≈3.085 [m].