To maintain a speed of 80   km   h - 1 by a bus of mass 500   kg on a plane rough road for 4   km distance, the work done by the engine of the bus will be _____ kJ . [The coefficient of friction between tyre of bus and road is 0 . 04 ]

Question

To maintain a speed of 80 &#160; km &#160; h - 1 by a bus of mass 500 &#160; kg on a plane rough road for 4 &#160; km distance, the work done by the engine of the bus will be _____ kJ . [The coefficient of friction between tyre of bus and road is 0 . 04 ]

Aicharya · Accepted Answer

It is given, v = 80 &#160; km &#160; h - 1 m = 500 &#160; kg S = 4 &#160; km &#956; = 0 . 04 The power due to friction is P f = F v where F = &#956; m g = 0 . 04 500 &#215; 9 . 8 &#215; 80 &#215; 5 18 &#160; W Hence, the work done by the engine in overcoming the friction is W = P f t = P f d v &#8658; W = 20 &#215; 9 . 8 &#215; 80 &#215; 5 18 &#215; 4 &#215; 10 3 80 &#215; 5 18 = 784 &#160; kJ

To maintain a speed of 80   km   h - 1 by a bus of mass 500   kg on a plane rough road for 4…

Solution

To maintain a speed of 80 &#160; km &#160; h - 1 by a bus of mass 500 &#160; kg on a plane rough road for 4…

Solution

To maintain a speed of 80 km h - 1 by a bus of mass 500 kg on a plane rough road for 4…