Answer:
0.45 seconds
Explanation:
Letting the value of g = 10 m/s/s
final velocity (v) = 0 m/s (since the egg will come to rest at the maximum height)
initial velocity(u) = 4.5 m/s
acceleration = -10 m/s/s (since the gravity is acting against the egg)
time = t seconds
From the first equation of motion:
<em>v = u + at</em>
<em>0 = 4.5 + (-10)t</em>
<em>t = -4.5 / -10</em>
t = 0.45 seconds
-- The net force on the box is 2N to the left.
-- The box will move to the left and accelerate to the left.
-- F=ma . a=F/m . a=(2N)/(4kg).
a = 0.5 m/s^2 to the left.
A fuse melts to protect a circuit.
Answer:
Explanation:
Initial height from the ground = .41 m
Final height = 1m
Height by which Kelli was raised ( h )= .59 m
When she passes through the lowest point , she loses P E
= mgh
= 440 x .59
= 259.6 J
kinetic energy possessed by her
= 1/2 mv²
= .5 x (440/9.8) x 2²
= 89.8 J
Difference of energy is lost due to work by air friction
work done by friction = 89.8 - 259.6
= - 169.8 J
