Mechanical Engineering - Strength of Materials - Discussion
Discussion Forum : Strength of Materials - Section 1 (Q.No. 8)
8.
Two shafts 'A' and 'B' transmit the same power. The speed of shaft 'A' is 250 r.p.m. and that of shaft 'B' is 300 r.p.m. The shaft 'B' has the greater diameter.
Discussion:
52 comments Page 3 of 6.
Neeraj chauhan said:
1 decade ago
Because velocity V = r*omega.
v = D/2*omega.
So v = D/2*2*pi*n.
D*n = v.
Now D is inversely proportional to n. So more R.P.M less diameter.
v = D/2*omega.
So v = D/2*2*pi*n.
D*n = v.
Now D is inversely proportional to n. So more R.P.M less diameter.
Vikash kumar said:
1 decade ago
The shaft having more speed will transmit less torque at same power level and for transmitting less torque less diameter shaft is required.
Vrushang said:
1 decade ago
P = F*V .
P = F*omega*r.
So if both shaft transmit same power then omega*r=constant so,
for same power omega increase radius decreases.
P = F*omega*r.
So if both shaft transmit same power then omega*r=constant so,
for same power omega increase radius decreases.
Karthik s said:
9 years ago
Da = 1.2Db,
Db = 0.833 D.
Here dia of the shaft B will be less compared to the diameter of the shaft A.
Hence the statement is false.
Db = 0.833 D.
Here dia of the shaft B will be less compared to the diameter of the shaft A.
Hence the statement is false.
Anil shukla said:
1 decade ago
According to formula Velocity #pi*d*N/60, where d is diameter of shaft, N is speed in rpm. Now N is inversely proportional to 'd'.
Sushant(dada) Patil said:
9 years ago
Speed is inversly proportional to diameter so shaft of greater daimeter should have less speed than that of smaller one.
Nemish said:
10 years ago
Power = Inertia*Angular velocity.
If angular velocity is increased, I would decrease to maintain same power.
If angular velocity is increased, I would decrease to maintain same power.
Navneet gupta said:
1 decade ago
Equate power of shaft A and shaft B.
On doing this you get Ta = 1.2Tb.
So diameter of B should be smaller.
On doing this you get Ta = 1.2Tb.
So diameter of B should be smaller.
Bhargav Panchal said:
7 years ago
v = π * D * N/60.
From this v is proportional to diameter and N both. So, I think the statement is true.
From this v is proportional to diameter and N both. So, I think the statement is true.
(1)
Priya said:
1 decade ago
As speed is inversely proportional to diameter so shaft b has higher speed than its dia must be lower.
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