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:

Explanation:
The centripetal acceleration of a point moving by circular motion is given by:

where
is the angular velocity
r is the distance from the axis of rotation
The point on the wheel makes 5.0 revolutions per second, so the frequency is

and the angular velocity is

While the distance of the point from the axis of rotation is

Substituting, we find the acceleration:

Answer:
V1 = ____0.3______ m/s, V2 = ____-0.3______ m/s,
p1 = ____0.015______ kg m/s, p2 = ___-0.015_______ kg m/s,
ptotal = _0___________ kg m/s
Explanation:
Taking the marble ball that moves from right to left as Marble 1 and the one that moves from left to right as Marble 2. We take direction from left to right as negative and from right to left as positive. Therefore, velocity of marble 1 will be +0.3 m/s while velocity of marble 2 will be -0.3 m/s. The mass of marble 1, m2 0.05 Kg and same to marble 2, m2=0.05 Kg
Momentum is product of mass and velocity hence using p to represent momentum
P1=0.05*0.3=0.015 Kg m/s
P2=0.05*-0.3=-0.015 Kg m/s
V1=0.3 m/s, V2=-0.3 m/s
The total momentum before collision will be the sum of P1 and P2 hence 0.015 Kg m/s+-0.015 Kg m/s=0
Ptotal=0 Kg m/s
Answer:
Power is the rate of using energy or doing work. Energy is measuredin Joules. Power is measured in Joules per second or Watts. Work can be defined as transfer of energy
V = 3.0 x 10⁸ m/s (This is the same for all types of electromagnetic waves)
f = 88.6 MHz = 8.86 x 10⁷ Hz
λ = ?
V = fλ
λ = V/f = (3 x 10⁸)/(8.86 x 10⁷)
= 3.4 m [Ans]
Hope this helps!