Answer:
His acceleration is 
Explanation:
Newton's second law states that acceleration of a body is cause by a net force, the relation between them is:
On the boy there're acting two forces, his weight (W) that points downward and the frictional force (f) that points upward (they boy moves downward and friction always is opposite to movement). So 
so (1) is:
Using the positive direction downward weight and gravitational acceleration(g) are positive and friction force is negative:
, solving for a:
, weight is mg:
Answer:
The momentum of block B = 27 Kg m/s
Explanation:
Given,
The initial momentum of block A, MU = 15 Kg m/s
The final momentum of block A, MV = -12 Kg m/s
Consider the block B is initially at rest.
Therefore, the initial momentum of block B, mu = 0
According to the laws of conservation of linear momentum, the momentum of the body before impact is equal to the momentum of the body after impact.
<em> MU + mu = MV + mv</em>
15 + (0) = (-12) + mv
mv = 15 + 12
= 27 Kg m/s
Hence, the momentum of the block B after impact is, mv = 27 Kg m/s
If the mass of the cylinder increases, the temperature of the water increases, because a greater mass means the cylinder has more potential energy that can be converted to thermal energy, increasing the temperature of the water.
Answer:
(a) 104 N
(b) 52 N
Explanation:
Given Data
Angle of inclination of the ramp: 20°
F makes an angle of 30° with the ramp
The component of F parallel to the ramp is Fx = 90 N.
The component of F perpendicular to the ramp is Fy.
(a)
Let the +x-direction be up the incline and the +y-direction by the perpendicular to the surface of the incline.
Resolve F into its x-component from Pythagorean theorem:
Fx=Fcos30°
Solve for F:
F= Fx/cos30°
Substitute for Fx from given data:
Fx=90 N/cos30°
=104 N
(b) Resolve r into its y-component from Pythagorean theorem:
Fy = Fsin 30°
Substitute for F from part (a):
Fy = (104 N) (sin 30°)
= 52 N
