Answer:
Correct answer: E total = 2,800 J
Explanation:
Given:
m = 4 kg the mass of the object
V = 20 m/s the speed (velocity) of the object
H = 50 m the height of the object above the surface
E total = ? J
The total energy of an object is equal to the sum of potential and kinetic energy
E total = Ep + Ek
Ep = m g H we take g = 10 m/s²
Ep = 4 · 10 · 50 = 2,000 J
Ek = m V² / 2
Ek = 4 · 20² / 2 = 2 · 400 = 800 J
E total = 2,000 + 800 = 2,800 J
E total = 2,800 J
God is with you!!!
The sound is perceived as louder if the amplitude increases, and softer if the amplitude decreases. As the amplitude of the sound wave increases, the intensity of the sound increases. Sounds with higher intensities are perceived to be louder.
Explanation:
In series combination
R = R1 + R2 + R3 + ...+ Rn
In parallel combination
1/R = 1/R1 + 1/R2 + 1/R3 + ...+ 1/Rn
Answer:
d. energy in an isolated system remains constant.
Explanation:
energy can neither be replaced or destroyed
Answer:
a = 0.827468
Explanation:
given,
half life of radium-224 = 3.66 days
now,

t is the time
A₀ is the amount at t = 0
at t = 0 , A(0) = 1
A(3.66) = 1/2
at t = 3.66


taking log both side
3.66 log (a) = log (0.5)
log a = -0.0822
now,
a = 0.827468