Answer:
The frictional torque is 
Explanation:
From the question we are told that
The mass attached to one end the string is 
The mass attached to the other end of the string is 
The radius of the disk is 
At equilibrium the tension on the string due to the first mass is mathematically represented as
substituting values
At equilibrium the tension on the string due to the mass is mathematically represented as
The frictional torque that must be exerted is mathematically represented as
substituting values
Answer:
a)= 98kJ
b)=108kJ
c) = 10kJ
Explanation:
a. The work that is done by gravity on the elevator is:
Work = force * distance
= mass * gravity * distance
= 1000 * 9.81 * 10
= 98,000 J
= 98kJ
b)The net force equation in the cable
T - mg = ma
T = m(g+a)
T = 1000(9.8 + 10)
T = 10800N
The work done by the cable is
W = T × d
= 10800N × 10
= 108000
=108kJ
c) PE at 10m = 1000 * 9.81 * 10 = 98,100 J
Work done by cable = PE +KE
108,100 J = KE + 98,100 J
KE = 10,000 J
= 10kJ
=
The yellow star will live longer as it has less mass
844J.
Assuming that there were no encumbrances during it's foreswing and it reached it's full potential at apogee.
Answer:
wavelength = 4 m
Explanation:
For distance 6 and 8m and speed of sound in air = c.
The travel time form the various distances 6 and 8 are 6/c and 8/c respectively.
cos(wt1) + cos(wt2) = 0
for a shift in phase t1 = t - 6/c,
t2 = t - 8/c
substituting t1 and t2
cos(π - w(t - 8/c)) = cos(w(t - 6/c))
solving using trigonometry identities in radians.
we have,
π - 2πn = w(t - 8/c) - w(t - 6/c)
putting w = 2πf
π - 2πn = 2πf(t - 8/c) - 2πf(t - 6/c)
dividing both sides by π
1 - 2n = 2ft - 16(f/c) - 2ft + 12(f/c)
simplifying we have,
1 - 2n = -4(f/c)
solving for f we have,
f = c/4(2n - 1)
putting n=1 and c = 343m/s
f = (343/4)*(2(1) - 1)
f = 85.75 Hertz
wave lenght = c/f , where c= speed of sound in air , f= frequency
wave lenght = 343/85.75 = 4m
