Recent content by Jamest39

A 45 degree angle?

In the direction of the rotation, between the tangential and centripetal acceleration vectors

right, so that allows us to use the equation ω=ω(initial) + αt, and since its staring from rest, the ω(initial is zero).

ω in terms of t, so (Δθ)/(Δt)

Since its starting from rest, it would be zero at t=0. Then after that, the tangential acceleration is given by rα or (Δω)/(Δt) and the centripetal acceleration is given by (ω^2)r

The angular velocity would be changing. But considering those as vectors, the direction would be constantly changing.

Homework Statement A solid sphere, starting from rest, rotates with constant angular acceleration α about a fixed axis passing through its center. Consider a particle within this sphere that lies at a perpendicular distance r from this axis. If, at some instant, the linear acceleration of this...

I can set ΣF = ma equal to the magnitude of the normal force?

So ΣF = ma, and the forces acting on it are gravity and the normal force. But how can I express mg in that formula when its at that position on the curve?

The centripetal acceleration? a = v^2/r

Yeah, question (a) was "Determine the speed of the mass at the instant when the mass is at position B." mgh = (1/2)mv^2 v = sqrt(2gh) h = R sin θ So, v = sqrt(2*9.8*0.66*sin48°) = 3.10 m/s

Homework Statement A 22-gram mass is released from rest at position A on a stationary frictionless surface whose shape is that of a quarter circle of radius R = 0.66 m. (b) Determine the magnitude of the normal force that acts on the mass when it is at position B (it is at position B when the...

Was my answer right or do I still have to factor in the energy he lost while going through the batter?

So, F = ma = (65 kg)(9.80 m/s^2) = 637 N W = Fscosθ = (637 N)(6.0 m)cos180° = -3822 J (6.0 as the displacement considering his whole movement?)

Homework Statement A 65-kg worker at a bakery loses his balance and falls 4.0 m before hitting the surface of a large vat of cake batter. He continues to travel downwards an additional 2.0 m before the cake batter finally brings him to rest. Calculate the work done on the worker by the cake...