Answer:
Speed, u = 29.4 m/s
Explanation:
Given that, A ball thrown straight up climbs for 3.0 sec before falling, t = 3 s
Let u is speed with which the ball is thrown up. When the ball falls, v = 0
Using first equation of motion as :
v = u + at
Here, a = -g
So, u = g × t

u = 29.4 m/s
So, the speed with which the ball was thrown is 29.4 m/s. Hence, this is the required solution.
The second one since you’re changing the soil up by adding different fertilisers. This will be you’re independent variable. And you’re dependent variable is your result = the plant height .
Hope this helps :)
Answer:
Distance of closest approach, 
Explanation:
It is given that,
Charge on proton, 
Charge on alpha particle, 
Mass of proton, 
Mass of alpha particle, 
The distance of closest approach for two charged particle is given by :



So, their distance of closest approach, as measured between their centers
. Hence, this is the required solution.
This is a classic example of conservation of energy. Assuming that there are no losses due to friction with air we'll proceed by saying that the total energy mus be conserved.

Now having information on the speed at the lowest point we can say that the energy of the system at this point is purely kinetic:

Where m is the mass of the pendulum. Because of conservation of energy, the total energy at maximum height won't change, but at this point the energy will be purely potential energy instead.

This is the part where we exploit the Energy's conservation, I'm really insisting on this fact right here but it's very very important, The totam energy Em was

It hasn't changed! So inserting this into the equation relating the total energy at the highest point we'll have:

Solving for h gives us:

It doesn't depend on mass!
Answer:
5.03 m
Explanation:
The wavelength of a wave is given by

where
v is the speed of the wave
f is the frequency of the wave
For the sonar signal in this problem,


Substituting into the equation, we find the wavelength:
