Answer:
v=77.62 m/s
Explanation:
Given that
h= - 300 m
speed of the bird ,u= 5 m/s
Lets take Speed of the berry when it hit the ground = v m/s
we know that ,if object is moving upward
v² = u² - 2 g h
u=Initial speed
v=Final speed
h=Height
Now by putting the values
v² = u² - 2 g h
v² = 5² - 2 x 10 x (-300) ( take g = 10 m/s²)
v² =25 + 20 x 300
v² ==25 + 6000
v² =6025
v=77.62 m/s
Therefore the final speed of the berry will be 77.62 m/s.
Answer:
<em>The fifth option is the correct answer: mv; 2 mv</em>
Explanation:
<u>Change of Momentum</u>
Assume an object has a momentum p1 and after some interaction it now has a momentum p2, the change of momentum is
The momentum is computed as
Where m is the mass of the object and v its speed. Now let's analyze the situation of both the ball and the clay.
The clay has an initial speed v and a mass m, thus its initial momentum is
When it hits the wall, it sticks, thus its final speed is 0 and
The change of momentum is
The absolute change is mv
Now for the ball, the initial condition is the same as it was for the clay, but the ball hits back at the same speed, thus its final momentum is
The change of momentum is
The absolute change is 2mv
The fifth option is the correct answer: mv; 2 mv