Answer:
Vy = V0 sin 38 where Vy is the initial vertical velocity
The ball will accelerate downwards (until it lands)
Note the signs involved if Vy is positive then g must be negative
The acceleration is constant until the ball lands
t (upwards) = (0 - Vy) / -g = Vy / g final velocity = 0
t(downwards = (-Vy - 0) / -g = Vy / g final velocity = -Vy
time upwards = time downwards (conservation laws)
Explanation:
It is given that,
Total mass is 70 kg
The truck exerts a constant force of 20 N.
Then the net force is given by :
F = ma
a is acceleration of rider

Initial velocity of rider is 0. So, using equation of kinematics to find the final velocity as :

Since, 1 m/s = 2.23 mph
4.28 m/s = 9.57 mph
So, the speed of the rider is 4.28 m/s or 9.57 mph.
Answer:
because he give heat and energy
First, we calculate the mass of Phosphorous present:
283.88 x 0.4364
= 123.88 amu
Atomic mass of P is 31 amu
moles of P = mass / Ar
= 123.88 / 31
= 4.0 moles
We know that one mole of substance has 6.02 x 10²³ particles
Atoms of P = 4 x 6.02 x 10²³
= 2.41 x 10²⁴ atoms