Answer:
<em>Speed of the electron is 2.46 x 10^8 m/s</em>
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Explanation:
momentum of the electron before relativistic effect = 
where 
is the rest mass of the electron
V is the velocity of the electron.
under relativistic effect, the mass increases.
under relativistic effect, the new mass M will be
M = 
where
c is the speed of light = 3 x 10^8 m/s
V is the speed with which the electron travels.
The new momentum will therefore be
==> 
It is stated that the relativistic momentum is 1.75 times the non-relativistic momentum. Equating, we have
1.75 =
the equation reduces to
1.75 = 
square both sides of the equation, we have
3.0625 = 1/
3.0625 - 3.0625
= 1
2.0625 = 3.0625
= 0.67
β = 0.819
substitute for
V/c = 0.819
V = c x 0.819
V = 3 x 10^8 x 0.819 = <em>2.46 x 10^8 m/s</em>
Answer:
5.125
Explanation:
formula for speed is distance/time distance measured in metres
Average speed is defined as the ratio of total distance covered in total given time
here we know that total distance that man moved is
so total distance is
now here total time of the motion is
total time will be given as
now by above formula
so his average speed is 30 km/h
Answer:
Time of flight A is greatest
Explanation:
Let u₁ , u₂, u₃ be their initial velocity and θ₁ , θ₂ and θ₃ be their angle of projection. They all achieve a common highest height of H.
So
H = u₁² sin²θ₁ /2g
H = u₂² sin²θ₂ /2g
H = u₃² sin²θ₃ /2g
On the basis of these equation we can write
u₁ sinθ₁ =u₂ sinθ₂=u₃ sinθ₃
For maximum range we can write
D = u₁² sin2θ₁ /g
1.5 D = u₂² sin2θ₂ / g
2 D =u₃² sin2θ₃ / g
1.5 D / D = u₂² sin2θ₂ /u₁² sin2θ₁
1.5 = u₂ cosθ₂ /u₁ cosθ₁ ( since , u₁ sinθ₁ =u₂ sinθ₂ )
u₂ cosθ₂ >u₁ cosθ₁
u₂ sinθ₂ < u₁ sinθ₁
2u₂ sinθ₂ / g < 2u₁ sinθ₁ /g
Time of flight B < Time of flight A
Similarly we can prove
Time of flight C < Time of flight B
Hence Time of flight A is greatest .
