-
A gear train shown in the figure consists of gears P, Q, R and S. Gear Q and gear R are mounted on the same shaft. All the gears are mounted on parallel shafts and the number of teeth of P, Q, R and S are 24,45, 30 and 80, respectively. Gear P is rotating at 400 rpm. The speed (in rpm) of the gear S is _______.
-
- 120 r.p.m.
- 121 r.p.m.
- 119 r.p.m.
- 122 r.p.m.
Correct Option: A
TP = 24
TQ = 45
TR = 30
TS = 80
NP = 400 rpm
NS =?
Here gear G is not meshing,
| = | = | | ...(i) | | NQ | TP | 24 |
| = | = | | ...(ii) | | NS | TQ | 45 |
By (i) and (ii)
| = | × | NS | 24 | 45 |
| NS = NP × | = | 80 | 80 |
NS = 120 r.p.m.
