GPE=mgh
m= 12.5kg
g= 9.81 always
h=?
568=12.5*9.81*h
Solve for h
You will get 4.63m
Answer:
Explanation:
A )
v² = u² + 2 a s
u = 0
s = 2.5
a = 9.8
v² = 2 x 9.8 x 2.5 = 49
v = 7 m /s
B )
time required to fall by first 2.5 m , t₁
s = 1/2 a t₁²
2.5 = .5 x 9.8 t₁²
t₁ = .714 s
time required to fall by 10 m
s = 1/2 a t₂²
10 = .5 x 9.8 t₂²
t₂ = 1.43 s
time required to fall by last 7.5 m
= t₂ - t₁
= 1.43 - .714
= .72 s
C )
time taken by second = .72 s
For second let initial velocity required be u
s = ut + 1/2 g t²
10 = u x .72 + .5 x 9.8 x .72²
10 = u x .72 + 2.54
u = 10.36 m /s
Answer:
thermometer is based on the principle of thermal expansion.
Answer:
The bond energy of F–F = 429 kJ/mol
Explanation:
Given:
The bond energy of H–H = 432 kJ/mol
The bond energy of H–F = 565 kJ/mol
The bond energy of F–F = ?
Given that the standard enthalpy of the reaction:
<u>H₂ (g) + F₂ (g) ⇒ 2HF (g)</u>
ΔH = –269 kJ/mol
So,
<u>ΔH = Bond energy of reactants - Bond energy of products.</u>
<u>–269 kJ/mol = [1. (H–H) + 1. (F–F)] - [2. (H–F)]</u>
Applying the values as:
–269 kJ/mol = [1. (432 kJ/mol) + 1. (F–F)] - [2. (565 kJ/mol)]
Solving for , The bond energy of F–F , we get:
<u>The bond energy of F–F = 429 kJ/mol</u>