Explanation:
formula for force is:
force=mass × acceleration
but in case of friction
force =coefficient of friction × Normal Reaction
F. = u × R
U = F/R
but when placed horizontally
R= M×G
M=mass=60kg
G=Gravity(10m/s or 9.8m/s)
F=140N
U=140/60×10
U=140/600
U=0.2333333333
approximately to 3 significant figures
U=0.233
if i am correct rate it 5 star
Answer:
28.81 m
Explanation:
Ff = -123
m * a = -123
(29.8+10.3) * a = -123
a = -123/40.1 = -3.07
We know,
v^2 = u^2 + 2as
0^2 = 13.3^2 + 2*(-3.07)*s
s = 176.89/6.14 = 28.81
[ If there's a problem with the solution, pleaase let me know ]
Explanation:
The internal heat sources for Jupiter and Saturn derive from primordial heat resulting from the initial gravitational contraction of each planet. Jupiter also generates heat by slow contraction, which liberates substantial gravitational energy. A significant part of Saturn’s heat comes from the release of gravitational energy from helium separating from the lighter hydrogen and sinking to its core. What one considers to be a star is a matter of definition, as we discuss in more detail in the chapter on The Birth of Stars and the Discovery of Planets outside the Solar System. While both Jupiter and Saturn generate much of their energy internally, they are not large enough (by a significant factor) to support nuclear reactions in their interiors, and so are not considered to be stars.
<span>A student hears a police siren.
The arithmetic of the Doppler Effect shows that if the distance between
the source and observer is changing, then the observer hears a different
frequency compared to the frequency actually radiating from the source.
Thus the first four choices would cause the student to hear a different
frequency:
-- if the student walked toward the police car
-- if the student walked away from the police car
-- if the police car moved toward the student
-- if the police car moved away from the student
The last two choices wouldn't affect the frequency heard by the student,
since the perceived frequency of a sound doesn't depend on its intensity.
-- if the intensity of the siren increased
-- if the intensity of the siren decreased.</span>
|---20----|
| |
| 50 |50
|---D--->|
Start End
Total displacement(D) 20 yards (East).