Answer:
v = 42.92 m/s
Explanation:
Given,
initial speed of the ball, v = 11 m/s
time taken to hit the ground = 5.5 m/s
velocity of the ball just before it hit the ground, v = ?
time taken by the ball to reach the maximum height
using equation of motion
v = u + at
final velocity = 0 m/s
0 = 11 - 9.8 t
t = 1.12 s.
time taken by the ball to reach the water from the maximum height
t' - 5.5 -1.12 = 4.38 s
using equation of motion for the calculation of speed just before it hit the water.
v = u + a t
v = 0 + 9.8 x 4.38
v = 42.92 m/s
Velocity of the ball just before it reaches the water is equal to v = 42.92 m/s
Answer:
m = 1.99 kg = 2 kg
Explanation:
The moment of inertia of a bicycle rim about it's center is given by the following formula:

where,
I = Moment of Inertia of the Bicycle Rim = 0.21 kg.m²
r = Radius of the Bicycle Rim = Diameter of the Bicycle Rim/2
r = 0.65 m/2 = 0.325 m
m = Mass of the Bicycle Rim = ?
Therefore,

<u>m = 1.99 kg = 2 kg</u>
Coal, petroleum, and natural gas are considered nonrenewable because they can not be replenished in a short period of time
Answer:
proof in explanation
Explanation:
First, we will calculate the number of half-lives:

where,
n = no. of half-lives = ?
t = total time passed = 2100 million years
= half-life = 700 million years
Therefore,

Now, we will calculate the number of uranium nuclei left (
):

and the rest of the uranium nuclei will become thorium nuclei (
)

dividing both:

<u>Hence, it is proven that after 2100 million years there are seven times more thorium nuclei than uranium nuclei in the rock.</u>