Answer:
The velocity must be reduced to one third to stay on the road
Explanation:
The sideways force that friction must resist comes from the centrifugal acceleration due to the turn.
fc=mv2Rfc=mv2R
the frictional force is given by
ff=μmgff=μmg where μμ is the static friction coefficient
if the car is not to skid
fc≤fffc≤ff so
mv2R≤μmgmv2R≤μmg
v≤μgR−−−−√v≤μgR
thus vv varies as the square root of μμ
so if μμ is reduced by 9, vv must be reduced by 9–√=39=3
and thus the speed must be reduced to<u> 26</u> m/s
3
Answer:
9.38J
Explanation:
mass = 0.425kg
height (h) = 2.25m
g = 9.81m/s^2
Gravitational potential energy (PE) = mgh
Plug in all info you got:
(0.425kg)(9.81m/s^2)(2.25m) = 9.38J
Answer:
the velocity at point B is 27120.08 km/hr
Explanation:
check the picture attached for explanation
F=-ks
F=-(390)(.45)
F=-175.5 N
Work=force x displacement
Work= 175.5(0.45)
Work= 78.98 J
Work = ∆E =78.98 J
Answer=79J (first option)