Answer:
C. 3.00 s
Explanation:
Given:
Δy = 1.80 m − 46.0 m = -44.2 m
v₀ = 0 m/s
a = -9.8 m/s²
Find: t
Δy = v₀ t + ½ at²
-44.2 m = (0 m/s) t + ½ (-9.8 m/s²) t²
t = 3.00 s
So we want to know what is the age of igneous rock if it contains one half of its original amount of potassium 40. The half-life of potassium 40 is 1.251*10^9 years. Since in the igneous rock there is one half of potassium left it means only one half-life has passed. And its age is 1.251*10^9 years or 1.251 billion years.
The wall will push back with an equal and opposite force, as defined by Newton's Third Law, so the wall will exert -200 N of force
Answer:
6kg
Explanation:
According to conservation of kinetic energy
m1u1+m2u2 = (m1+m2)v
m1 and m2 are the masses of the bodies
u1 and u2 are the initial velocities
v is the final velocity
Given
m1 =2kg
u1 = 8.0m/s
m2 = ?
u2 = 0m/s (second ice at rest)
v = 2.0m/s
Substitute into the formula
2(8)+m2(0) = (2+m2)(2)
16+0 = 4+2m2
16-4= 2m2
12 = 2m2
m2 =12/2
m2 = 6kg
Hence the mass of the second block is 6kg
Answer:
D) either 436 Hz or 444 Hz
Explanation:
frequency of the tuning fork, F₁ = 440 Hz
frequency of the piano, F₂ = ?
Beat frequency, F = 4 Hz
Beat frequency is given as the difference between the frequency of the two instruments and it is given by;
F = F₂ - F₁ or F = F₁ - F₂
F₂ = F + F₁ or F - F₁ = - F₂
F₂ = 4 Hz + 440 Hz or 4 - 440 = - F₂
F₂ = 444 Hz or - 436 = - F₂
F₂ = 444 Hz or F₂ = 436 Hz
Therefore, the frequency of the piano is 444 Hz or 436 Hz
