The atomic number of beryllium (Be) is 4, and the atomic number of barium (Ba) is 56. the <span>comparison is best supported by this information is that beryllium has a lower atomic radius than Barium</span>
Answer:
78.4 m
Explanation:
Using newton's equation of motion,
S = ut + 1/2gt²......................... Equation 1
Where S = Height, t = time, u = initial velocity, g = acceleration due to gravity.
Note: Taking upward to be negative, and down ward positive
Given: u = 49 m/s, t = 2.0 s, g = -9.8 m/s²
Substitute into equation 1
S = 49(2) - 1/2(9.8)(2)²
S = 98 - 19.6
S = 78.4 m
Hence the height of the ball two seconds later = 78.4 m
Answer:
The true weight of the aluminium is
4.5021 kg
Explanation:
Given data
= 4.5 kg
= 1.29 
= 2.7× 
The true mass of the aluminium is given by

Put all the values in above equation we get

4.5021 kg
Therefore the true weight of the aluminium is
4.5021 kg
v = initial velocity of launch of the stone = 12 m/s
θ = angle of the velocity from the horizontal = 30
Consider the motion of the stone along the vertical direction taking upward direction as positive and down direction as negative.
v₀ = initial velocity along vertical direction = v Sinθ = 12 Sin30 = 6 m/s
a = acceleration of the stone = - 9.8 m/s²
t = time of travel = 4.8 s
Y = vertical displacement of stone = vertical height of the cliff = ?
using the kinematics equation
Y = v₀ t + (0.5) a t²
inserting the values
Y = 6 (4.8) + (0.5) (- 9.8) (4.8)²
Y = - 84.1 m
hence the height of the cliff comes out to be 84.1 m
⚡️⚡️⚡️Kinetic energy ⚡️⚡️⚡️