Answer:
No, the sound produced by screeching brakes is not a useful form of energy, because it does not contribute to stopping the car.
I think the correct answer from the choices would be that metals donate electrons to nonmetals. Ionic bonding involves transfer of valence electrons. The metal looses its valence electrons which makes it a cation while the nonmetal accepts these electrons.
Answer:
top speed = 17.25
Total height = 281.19 m
Explanation:
given data
mass = 75 kg
thrust = 160 N
coefficient of kinetic friction = 0.1
solution
we get here frictional force acting that is
frictional force =
.............1
frictional force = 0.1 × 75 × 9.8
frictional force = 73.5 N
and
Net force acting will be F = 160 - 73.5 N
F = 86.5 N
so
Acceleration in the First 15 second will be
F = ma .........2
86.5 = 75 × a
a = 1.15 m/s²
and
now After 15 second the velocity will be as
v = u + at ..........3
here u is 0
so v will be
V = 1.15 × 15
v = 17.25
and
now we get travels distance S in 15 s
s = u × t + 0.5 × a × t²
here u is 0
so distance s will be
s = 0.5 × a × t²
s = 0.5 × 1.15 × 15²
s = 129.37 m
and
now acceleration acting is
F =
m a =
a = 
a = - 0.98
here it is negative it mean downward nature of acceleration
and
now we get distance s by this formula
V² - u² = 2 a s
here v velocity is 0 and
u initial velocity is 17.25 m/s
put here value
0 - 17.25² = 2 × (-0.98) × s
solve it we get
s = 151.82 m
so
Total height is
Total height = 129.37 m + 151.82 m
Total height = 281.19 m
Because it’s made of metal. And metal is a good conductor
Answer:
The well is 23.3 m
Explanation:
As the bucket is lifted out of the well, energy in the man is being transferred to the bucket as gravitational potential energy.
Work done against gravity = mass * height * acceleration due to to gravity
W = mgh
5 920 J = 25.9 kg * h * 9.8 m/s²
h = 23.3 m