To answer this problem, we will use the equations of motions.
Part (a):
For the ball to start falling back to the ground, it has to reach its highest position where its final velocity will be zero.
The equation that we will use here is:
v = u + at where
v is the final velocity = 0 m/sec
u is the initial velocity = 160 m/sec
a is acceleration due to gravity = -9.8 m/sec^2 (the negative sign is because the ball is moving upwards, thus, its moving against gravity)
t is the time that we want to find.
Substitute in the equation to get the time as follows:
v = u + at
0 = 160 - 9.8t
9.8t = 160
t = 160/9.8 = 16.3265 sec
Therefore, the ball would take 16.3265 seconds before it starts falling back to the ground
Part (b):
First, we will get the total distance traveled by the ball as follows:
s = 0.5 (u+v)*t
s = 0.5(160+0)*16.3265
s = 1306.12 meters
The equation that we will use to solve this part is:
v^2 = u^2 + 2as where
v is the final velocity we want to calculate
u is the initial velocity of falling = 0 m/sec (ball starting falling when it reached the highest position, So, the final velocity in part a became the initial velocity here)
a is acceleration due to gravity = 9.8 m/sec^2 (positive as ball is moving downwards)
s is the distance covered = 1306.12 meters
Substitute in the above equation to get the final velocity as follows:
v^2 = u^2 + 2as
v^2 = (0)^2 + 2(9.8)(1306.12)
v^2 = 25599.952 m^2/sec^2
v = 159.99985 m/sec
Therefore, the velocity of the ball would be 159.99985 m/sec when it hits the ground.
Acceleration = v-u/t
= (45-30)/15
= 1 km/h
Distance = ut + 1/2 at^2
s = [30 x 15] + 1/2 x 1 x 15^2
= 562.5 km
Hope this helps
Answer:
The best reason for the increased risk of cardiovascular diseases in women after menopause is the significant decrease in the levels of Estrogen in the body.
Detailed answer:
- Due to the approach of menopause the estrogen levels in the blood decrease drastically.
- Estrogen helps in relaxing the vessels and keeping them in their natural diameter.
- But due to a drastic decrease in its level due to menopause, there is a high chance of cholesterol building up on the walls of the artery in the heart, which can cause many cardiovascular diseases.
Complete Question
A truck going 15 km/h has a head-on collision with a small car going 30 km/h. Which statement best describes the situation?
A. the truck has the greater change of momentum because it has the greater mass
B. the car has the greater change of momentum because it has the greater speed
C. neither the car nor the truck changes its momentum in the collision because momentum is conserved
D. they both have the same change in magnitude of momentum because momentum is conserved
E. none of the above is necessarily true
Answer:
D. They both have the same change in magnitude of momentum because momentum is conserved
Explanation:
In order to get a good understanding of the solution above we define some
concetps
Momentum
This is defines quantified motion and can be mathematically represented as
Momentum = Mass of the body × Velocity of the body
According to the Law of conservation of momentum states that when two particles collide together in a system that is being isolated that their total momentum before and after their collision is equal this means that the momentum lost by the truck would be the same as the momentum gained by the small car
The answer here is <span>The government is expansive</span>
