A quick, easy way to decide whether there was a chemical change
is to look and see whether there are NEW substances after the
event, that weren't there when it started.
This particular scenario started out with fat and sodium hydroxide (lye).
And then, suddenly, POOF ! Soap and glycerin showed up. Where did
THOSE come from ? They came from the molecules in fat and lye,
getting broken up and recombined to make different substances.
THAT's exactly a chemical change.
Answer:
7350 J
Explanation:
Gravitational Potential Energy: This is defined as the energy possessed by a body due to it's position in the gravitational field. The S.I unit is Joules(J).
Applying,
E.p = mgh..................... Equation 1
Where E.p = Gravitational potential Energy, m = mass of the object, h = height of the object above the surface of the earth, g = acceleration due to gravity.
Given: m = 2.5 kg, h = 300 m
Constant: g = 9.8 m/s²
Substitute these values into equation 1
E.p = 2.5(300)(9.8)
E.p = 7350 J.
Im 99% sure
tan^-1 (6.2/22)= 15.7º
with 2 significant figures 16º
Work done = force x distance
work done = 15 x 3
work done = 45J
Answer
given,
Mass of the runner, M = 70 Kg
speed of the runner on the second base = 4.35 m/s
speed at the base = 0 m/s
Acceleration due to gravity,g = 9.8 m/s²
a) magnitude of mechanical energy lost
Mechanical energy lost is equal top gain in kinetic energy
b) Work done = Force x displacement
W = F. x
F = μ mg
W = μ mg . x
Work done is equal to 662.29 J
using the coefficient of the friction,μ = 0.7
x = 1.38 m
Hence, the runner will slide to 1.38 m.
