Answer:
the work done by gravity on the boy is 604.62 J
Explanation:
Given;
distance the boy slides, d = 3 m
angle of inclination of the playground, θ = 40⁰
mass of the boy, m = 32 kg
The vertical height, h, above the ground through which the boy falls represents the height of the triangle which is the opposite side.
The distance through which the boy slides, d, represents the hypotenuse side of the right triangle.
The work done by gravity on the boy is calculated as;
W = P.E = mgh
= 32kg x 9.8m/s² x 1.928m
= 604.62 J
Therefore, the work done by gravity on the boy is 604.62 J
The potential energy is most often referred to as the "energy at rest" and is dependent on the elevation of an object. This can be calculated through the equation,
E = mgh
where E is the potential energy, m is the mass, g is the acceleration due to gravity, and h is the height. In this item, we are not given with the mass of the cart so we assume it to be m. The force is therefore,
E = m(9.8 m/s²)(0.5 m) = 4.9m
Hence, the potential energy is equal to 4.9m.
The car travels a distance of
(8.0 m/s) (5 s) + 1/2 (10.0 m/s²) (5 s)² = 165 m
Answer:
Explanation:
a ) When the box starts to slip
static friction = mg sinα
mg cosα x μ = mg sinα ( μ is coefficient of static friction )
Tanα = μ = .35
α = 19.2°
b ) Once box starts moving , kinetic friction will start applying on it
kinetic friction = mg cos19.2 x .25
= 2.31m
net force downward = mgsin19.2 - mgcos19.2 x .25
= m ( 3.22 - 2.31 )
= .91 m
acceleration downward ( a ) = .91 m / s²
c )
v² = u² + 2 a s
= 0 + 2 x .91 x 5
= 9.1
v = 3 m / s
