Respuesta :
Answer:
When he weight of the car is 8.55 x [tex]10^{3}[/tex] N then power = 314.012 KW
When he weight of the car is 1.10 x [tex]10^{4}[/tex] N then power = 43.76 KW
Explanation:
Given that
Initial velocity [tex]V_{1}[/tex] = 0
Final velocity [tex]V_{2}[/tex] = 24.8 [tex]\frac{m}{s}[/tex]
Time = 7.88 sec
We know that power required to accelerate the car is given by
P = [tex]\frac{change \ in \ kinetic \ energy}{time}[/tex]
Change in kinetic energy Δ K.E = [tex]\frac{1}{2} m (V_{2}^{2} - V_{1}^{2} )[/tex]
Since Initial velocity [tex]V_{1}[/tex] = 0
⇒ Δ K.E = [tex]\frac{1}{2} m V_{2} ^{2}[/tex]
⇒ Power P = [tex]\frac{1}{2} \frac{m}{t} V_{2} ^{2}[/tex]
⇒ Power P = [tex]\frac{1}{2} \frac{W}{g\ t} V_{2} ^{2}[/tex] -------- (1)
(a). The weight of the car is 8.55 x [tex]10^{3}[/tex] N = 8550 N
Put all the values in above formula
So power P = [tex]\frac{1}{2} \frac{8550}{(9.81)\ (7.88)} (24.8) ^{2}[/tex]
P = 314.012 KW
(b). The weight of the car is 1.10 x [tex]10^{4}[/tex] N = 11000 N
Put all the values in equation (1) we get
P = [tex]\frac{1}{2} \frac{11000}{(9.81)\ (7.88)} (24.8) ^{2}[/tex]
P = 43.76 KW
