A 500 kg car climbs a road with gradient 1 in 49 at constant speed 54 km/h. Engine power is 4 kW. Find frictional force (N), take g≈9.8 m/s².
Physics · Mixed Chapter
JEE Main Practice

Question

A 500 kg car climbs a road with gradient 1 in 49 at constant speed 54 km/h. Engine power is 4 kW. Find frictional force (N), take g≈9.8 m/s².

G1 Physics · Accepted Answer

Step 1: Convert speed: v=54×(5/18)=15 m/s. Step 2: Total opposing force from P=Fv is F=P/v=4000/15≈266.7 N. Step 3: Downhill gravity component on a 1-in-49 gradient is mg sinθ≈500×9.8/49=100 N. Step 4: Friction=f=266.7−100≈166.7 N.