Explanation:
Given that,
Force with which a child hits a ball is 350 N
Time of contact is 0.12 s
We need to find the impulse received by the ball. The impulse delivered is given by :

So, the impulse is 42 N-m..
We know that he change in momentum is also equal to the impulse delivered.
So, impulse = 42 N-m and change in momentum =42 N-m.
Answer:
the expected distance is 4.32 m
Explanation:
given data
half life time = 1.8 ×
s
speed = 0.8 c = 0.8 × 3 ×
to find out
expected distance over
solution
we know c is speed of light in air is 3 ×
m/s
we calculate expected distance by given formula that is
expected distance = half life time × speed .........1
put here all these value
expected distance = half life time × speed
expected distance = 1.8 ×
× 0.8 × 3 ×
expected distance = 4.32
so the expected distance is 4.32 m
Answer:
The minutes hand travels 39.60 cm.
Explanation:
Note: a clock has a shape of a circle, the minutes hand is the radius, and the travel of the minutes hand forms a arc.
Length of an arc = ∅/360(2πr)
L = ∅/360(2πr).................... Equation 1π
Where L = length of an arc, ∅ = angle formed by an arc, r = radius of the arc.
Given: ∅ = 252°, r = 9 cm, π = 3.143.
Substituting these values into equation 1,
L = 252/360(2×3.143×9)
L = 0.7×2×3.143×9
L = 39.60 cm.
Thus the minutes hand travels 39.60 cm.
Answer:
option C
Explanation:
given,
energy dissipated by the system to the surrounding = 12 J
Work done on the system = 28 J
change in internal energy of the system
Δ U = Q - W
system losses energy = - 12 J
work done = -28 J
Δ U = Q - W
Δ U = -12 -(-28)
Δ U = 16 J
hence, the correct answer is option C
The molar latent enthalpy of boiling of iron at 3330 K is ΔH = 342
10^3 J.
<u>Explanation:</u>
Molar enthalpy of fusion is the amount of energy needed to change one mole of a substance from the solid phase to the liquid phase at constant temperature and pressure.
d ln p = (ΔH / RT^2) dt
(1/p) dp = (ΔH / RT^2) dt
dp / dt = p (ΔH / RT^2) = 3.72
10^-3
(p) (ΔH) / (8.31) (3330)^2 = 3.72
10^-3
ΔH = 342
10^3 J.