Physics problem help please?
A car of mass 942.4 kg accelerates from rest with a constant power output of 140.5 hp. Neglecting air resistance, what is the speed of the car after 4.55 s?
A car of mass 942.4 kg accelerates from rest with a constant power output of 140.5 hp. Neglecting air resistance, what is the speed of the car after 4.55 s?
Comments
Using Power Formula;
P = Power in hp;
1hp = 746 watts
P = W / t
where; W= work, (joule)
t = time (s)
solving for W
W = P x t
W = 150.5 hp x 746 watts /hp ( 4.55 s ) watts = J/s
W = 510842.15 Joules
solving for velocity
W is consider to be the Kinetic energy of the car
K.E = 0.5 m v^2
substitute the value of W to K.E
510842.15 J = 0.5 ( 942.4 kg) v^2 J = Newton x meter
N = kg x m/ s^2
v = 32.93 m/ s -----> Final answer
Is it a Prius?