Answer:
28.5 m/s
18.22 m/s
Explanation:
h = 20 m, R = 20 m, theta = 53 degree
Let the speed of throwing is u and the speed with which it strikes the ground is v.
Horizontal distance, R = horizontal velocity x time
Let t be the time taken
20 = u Cos 53 x t
u t = 20/0.6 = 33.33 ..... (1)
Now use second equation of motion in vertical direction
h = u Sin 53 t - 1/2 g t^2
20 = 33.33 x 0.8 - 4.9 t^2 (ut = 33.33 from equation 1)
t = 1.17 s
Put in equation (1)
u = 33.33 / 1.17 = 28.5 m/s
Let v be the velocity just before striking the ground
vx = u Cos 53 = 28.5 x 0.6 = 17.15 m/s
vy = uSin 53 - 9.8 x 1.17
vy = 28.5 x 0.8 - 16.66
vy = 6.14 m/s
v^2 = vx^2 + vy^2 = 17.15^2 + 6.14^2
v = 18.22 m/s
As per impulse momentum theorem we know that

now here we will have

t = 1.30 ms
m = 0.144 kg

now we need to find final speed using above formula


so final speed is given as above
The correct definition of a fracture is break in the bone
<u>Explanation:</u>
When nay injury results in the breaking or causing any cracking in the bones of any parts then this will lead to fracture. When the injury caused is near the ligament or tissue in which the bone is connected or attached then it will lead to an avulsion fractures. Thus this will lead to the pulling of bone form the original position thereby leading more pain in the spot associated with the fracture.
Sports people are the victims of this type of fracture. Fracture may occur anywhere mostly legs,hands,ankle,hip and elbow. sometimes it may be in finger, shoulder,knee,etc. The main symptoms that are associated with fracture includes, selling, inability in moving the fractured part or pain associated when trying to move that part, Loss of the affected part's function,etc.
Let
be the height of the building and thus the initial height of the ball. The ball's altitude at time
is given by

where
is the acceleration due to gravity.
The ball reaches the ground when
after
. Solve for
:


so the building is about 16 m tall (keeping track of significant digits).
Answer:
F=5449 N
Explanation:
Work done is a product of force and displacement ie
Work done, W, = Force*Displacement
Power, P, is Work done/Time
where P is power, W is work done, F is force, S is displacement and t is time
In this case, F is the frictional force. Converting the power from hp to W, we multiply by 746 hence P=746*168=125328 W
Since displacement/time is velocity, then
P=FV where V is velocity in m/s
Making F the subject


F=5449 N