Hello!
Use the equation for momentum:
Plug in the given mass and velocity into the equation:
Answer:
D. the linear velocity of the point of contact (relative to the inclined surface) is zero
Explanation:
The force of friction emerges only when there is relative velocity between two objects . In case of perfect rolling , there is no sliding so relative velocity between the surface and the point of contact is zero . In other words the velocity of point of contact becomes zero , even though , the whole body is in linear motion . It happens due point of contact having two velocities which are equal and opposite . One of the velocity is in forward direction and the other velocity which is due to rotation is in backward direction . So net velocity of point of contact becomes zero . Due to absence of sliding , displacement due to friction becomes zero . Hence work done by friction becomes zero.
Answer:
The power dissipated in the 3 Ω resistor is P= 5.3watts.
Explanation:
After combine the 3 and 6 Ω resistor in parallel, we have an 2 Ω and a 4 Ω resistor in series.
The resultating resistor is of Req=6Ω.
I= V/Req
I= 2A
the parallel resistors have a potential drop of Vparallel=4 volts.
I(3Ω) = Vparallel/R(3Ω)
I(3Ω)= 1.33A
P= I(3Ω)² * R(3Ω)
P= 5.3 Watts