Answer:
a)
b)
c)
d)
e)
Explanation:
Given that:
- initial speed of turntable,
- full speed of rotation,
- time taken to reach full speed from rest,
- final speed after the change,
- no. of revolutions made to reach the new final speed,
(a)
∵ 1 rev = 2π radians
∴ angular speed ω:
where N = angular speed in rpm.
putting the respective values from case 1 we've
(c)
using the equation of motion:
here α is the angular acceleration
(b)
using the equation of motion:
(d)
using equation of motion:
(e)
using the equation of motion:
Answer:
r1 = 5*10^10 m , r2 = 6*10^12 m
v1 = 9*10^4 m/s
From conservation of energy
K1 +U1 = K2 +U2
0.5mv1^2 - GMm/r1 = 0.5mv2^2 - GMm/r2
0.5v1^2 - GM/r1 = 0.5v2^2 - GM/r2
M is mass of sun = 1.98*10^30 kg
G = 6.67*10^-11 N.m^2/kg^2
0.5*(9*10^4)^2 - (6.67*10^-11*1.98*10^30/(5*10^10)) = 0.5v2^2 - (6.67*10^-11*1.98*10^30/(6*10^12))
v2 = 5.35*10^4 m/s
Answer:
70.07 Hz
Explanation:
Since the sound is moving away from the observer then
and when moving towards observer
With of 76 then taking speed in air as 343 m/s we have
Similarly, with of 65 we have
Now
v_s=27.76 m/s
Substituting the above into any of the first two equations then we obtain