The problem is fairly simple if you use the formula.
Formula: Force = (mass) x (acceleration)
3 x 5 = 15 newtons
Note: 3 kg is the mass of the skateboard, and 5 m/s2 is the acceleration.
Answer: 15 newtons
It is fiery because it is cooled molten magma
Answer:

Explanation:
k = Coulomb constant = 
v = Velocity of electron = 
q = Charge of electron = 
m = Mass of electron = 
r = Radius
The electrical and centripetal force will balance each other

The radius of the orbital is 
Required value of initial speed of the bullet be ( 4M/m)√(gL).
Given parameters:
Mass of the bullet =m.
Mass of the bob of the pendulum = M.
speed of the bullet before collision = v
Speed of the bullet after collision = v/2.
Length of the pendulum stiff rod = L.
Let speed transmitted to the pendulum be u.
Using principle of conservation of momentum:
mv = Mu + mv/2
⇒ Mu = mv/2
⇒ u = (m/M)v/2
We know that: to make the bob over the top of the trajectory without falling backward in its circular path, required speed be = √(4gL). [ where g = acceleration due to gravity]
To be minimum initial speed the bullet must have in order for the pendulum bob to just barely swing through a complete vertical circle:
u = √(4gL)
⇒ (m/M)v/2 = √(4gL)
⇒ v =( 4M/m)√(gL).
Hence, minimum required speed of the bullet be ( 4M/m)√(gL).
Learn more about speed here:
brainly.com/question/28224010
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