I thought you needed it because theta is the angle between the force vector and the velocity vector.
No?
It changes the answer a lot without it. 90*50 = 4.5*10^3 I got 4.5*10^2
Homework Statement
A bicyclist coasts down a 7.0 degree slope at a steady speed of 5.0 m/s. Assuming a total mass of 75 kg (bicycle plus rider), what must the cyclist's power output be to pedal up the same slope at the same speed?
Homework Equations
P=Fvcos\theta
K=\frac{1}{2}mv^2...
Also, if the speed of the mass is 2 m/s @ x=2 what is the speed at x=6?
KE=\frac{mv^2}{2}
1600=\frac{(1)(v^2)}{2} => v=5.6*10^1 = 60 m/s
Would that be correct?
Homework Statement
A force given by F(x)=5x^3 (in \frac {N}{m^3}) acts on a 1-kg mass moving on a frictionless surface. The mass moves from x = 2m to x = 6m.
a) How much work is done by the force?
Homework Equations
W=\int F_x from x_o to x_f
The Attempt at a Solution
\int 5x^3 from...
Homework Statement
Two railroad cars, each with a mass of 7,000kg and traveling at 90 km/h collide head on and come to rest. How much mechanical energy is lost in this collision?
Homework Equations
KE=\frac{1}{2}mv^2
The Attempt at a Solution...