An airplane is traveling 735 km/h in a direction 41.5° west of north (Fig. 3–31). (a) Find the components of the velocity vector in the northerly and westerly directions. (b) How far north and how far west has the plane traveled after 3.00 h?

FIGURE 3–31

Solution 9P Introduction Given in the question that 25% of chemical energy is converted to mechanical energy. Therefore, remaining (100-25)% = 75% will be mechanical energy as Total energy = Chemical energy+mechanical energy. To calculate increase in body temperature, we need to use the equation Q = ms, where Q is amount of heat involved, m is the mass of J cyclist, s is specific heat of human body = 3400 kg. C, is increase in body temperature. Step 1: Total metabolic power is = 480 W Now, 75% of total metabolic power is converted to thermal energy. Step 2: Therefore, the rate of conversion of chemical energy to thermal energy = 75% of 480 W = 100×480 W 3600 = 10 W = 360 W Let us denote this thermal power as P . to, We have P = 360tW . Time t = 10 min = 10×60 s ( since, 1 min = 60 s) = 600 s Therefore, thermal energy utilized is Q = P ×t t Q = 360×600 Ws Q = 360×600 J …..(1)