Answer:
F = 39.36 N
Explanation:
given,
initial speed, u = 38 m/s
final speed, v = 0 m/s
mass of ball = 0.145 Kg
time, t = 0.14 s
Force = ?
using impulse formula
J = change in momentum
J = F x t
m(v - u) = F x t
0.145 x (0 - (-38)) = F x 0.14
F x 0.14 = 5.51
F = 39.36 N
force exerted by the ball is equal to 39.36 N.
Given that,
Radius of track, r = 50 m
time , t = 9 s
velocity, v = ?
Distance covered by car in one lap around a track is equal to the circumference of the track.
C = 2 π r = 2 * 3.14 * 50
C = 314.159 m
Distance covered by car, s = 314.159 m
Velocity = distance/ time
V = 314.159 / 9
V = 34.9 m/s
The average velocity of car is 34.9 m/s.
Answer:
The sea level will be 5m higher in 1667 y (years)
Explanation:
From the question, the rate at which the ocean's level is currently rising is about 3mm per year.
First, we will convert mm (millimeter) to m (meter)
1 mm = 0.001 m
Then,
3 mm = 3 × 0.001 m
= 0.003m
That is, the rate at which the ocean's level is currently rising is about 0.003m per year.
Now, to determine how long it will take for the ocean's level be 5 m higher than now at the given rate,
If the ocean rises 0.003 m in 1 year, then
the ocean will rise 5 m in x years
x = (5 m × 1 year) / 0.003 m
x = 5 / 0.003
x = 1666.67 years
x ≅ 1667 years
Hence, the sea level will be 5m higher in 1667 y (years)
