Answer:
True.
Explanation:
If the sum of the external forces on an object is zero, then the sum of the external torques on it must also be zero.
The net external force and the net external torque acting on the object have to be zero for an object to be in mechanical equilibrium.
Hence, the given statement is true.
Answer:
Acceleration
Explanation:
The quantity of the rate of change of velocity is termed the acceleration of the body.
Acceleration is the rate of change of velocity with time;
A = 
A is the acceleration
v is the final velocity
u is the initial velocity
t is the time taken
Answer: 18.27°
Explanation:
Given
Index of refraction of blue light, n(b) = 1.64
Wavelength of blue light, λ(b) = 440 nm
Index of refraction of red light, n(r) = 1.595
Wavelength of red light, λ(r) = 670 nm
Angle of incident, θ = 30°
Angle of refraction of red light is
θ(r) = sin^-1 [(n(a)* sin θ) / n(r)], where n(a) = index of refraction of air = 1
So that,
θ(r) = sin^-1 [(1 * sin 30) / 1.595]
θ(r) = sin^-1 (0.5 / 1.595)
θ(r) = sin^-1 0.3135
θ(r) = 18.27°
Explanation:
KE = 1/2*m*v^2
mass won't change
but velocity is
A: the force is pushing against the direction of the object, so velocity is decreasing, so KE is decreasing
B: the F net line is pretty much straight up, which means there is no net force pushing to the left, but velocity is still increasing
Why? Because if you use the pythagorean theorem, the hypotenuse is always longer than the legs.
Note: velocity only ever stays the same if there is no net force (or 0 acceleration), so all four of these are either decreasing or increasing
C: there is a net force to the right, so velocity is increasing
D: There is a net force to the right but velocity is to the left, so velocity is decreasing
Hope I got these right
