Isotopes of an element will contain the same number of protons and electrons but will differ in the number of neutrons they contain. In other words, isotopes have the same atomic number because they are the same element but have a different atomic mass because they contain a different number of neutrons
Answer:
The speed with which the baseball leaves the hand = 20.58 m/s
Explanation:
The time take to reach highest height during a projectile's flight is given by
t = (u sin θ)/g
u = initial velocity of the baseball = ?
θ = angle of throw above the horizontal
g = acceleration due to gravity = 9.8 m/s²
1.05 = (u sin 30)/9.8
u = (1.05 × 9.8)/0.5
u = 20.58 m/s
Answer:
(I). The time at highest point 4.0 sec.
(II). It returns to back to its original height in 8.1 sec
Explanation:
Given that,
Velocity 
(I). We need to calculate the time at highest point
Using equation of motion

Where, v = final velocity
u = initial velocity
g = acceleration due to gravity
t = time
Put the value into the formula




(II). We know that, when the ball to travel from the initial point and reached at initial point then the displacement is zero.
We need to calculate the total time when it returns to back to its original height
Using equation of motion

Where, s = displacement
g = acceleration due to gravity
t = time
u = velocity
Put the value in the equation



Hence. (I). The time at highest point 4.0 sec.
(II). It returns to back to its original height in 8.1 sec