According to given condition there is no height(m) given from roof of building to the ground, there height given 18 m at a point above the ground. So, h=18m , mass=3kg , g=9.8m/s2 P.E=mgh P.E=(3)(9.8)(18) P.E=529J
Answer:
u = 25 m/s
Explanation:
given,
length of skid = 93 m
coefficient of friction = 0.35
final velocity = 0 m/s
initial velocity = ?
force here is friction f = μ mg
F = ma
now com paring
-μ mg = m a
a = - μ g
a = - 0.35 x 9.8
a = -3.43 m/s²
we know,
v² = u² + 2 a s
0 = u² - 2 x 3.43 x 93
u² = 637.98
u = 25.26 m/s
u = 25 m/s (two significant figure)
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