Explanation:
1.<u>Seeds have endosperm which provides nourishment for a new plant, but spores do not have any stored food supplies.</u>
hope it helpful
A projectile fired upward from the Earth's surface will usually slow down, come momentarily to rest, and return to Earth. For a certain initial speed, however it will move upward forever, with its speed gradually decreasing to zero just as its distance from Earth approaches infinity. The initial speed for this case is called escape velocity. You can find the escape velocity v for the Earth or any other planet from which a projectile might be launched using conservation of energy. The projectile of mass m leaves the surface of the body of mass M and radius R with a kinetic energy Ki = mv²/2 and potential energy Ui = -GMm/R. When the projectile reaches infinity, it has zero potential energy and zero kinetic energy since we are seeking the minimum speed for escape. Thus Uf = 0 and Kf = 0. And from conservation of energy,
Ki + Ui = Kf + Uf
mv²/2 -GMm/R = 0
∴ v = √(2GM/R)
This is the expression for escape velocity.
Answer:
Force F = 69.35 N
Explanation:
given data
Ball Initial speed u = 0
Ball Final speed v = 42.1 m/s
average power generate = 2920 W
solution
Power generate is express as
P= 
..............1
here W is work done and t is time
and work w = F × d
so
P= 
and we know speed v = 
so here
Power P = F × v
put here value and we get force
Force F = 
Force F = 69.35 N
Haven't taken physics but I would assume if her friend is standing in front of her that you would add up the speeds and get 30 km/hr.
