Answer:

Explanation:
According to the newton's second law of motion we can apply F=ma hear
Force = mass * acceleration
(assume the piano is moving left side )
←F = ma

The sound is increased because sound waves are in fact mech. waves which means the that they can't travel through empty space and thus need a medium to travel through
Answer:
Diameter decreases by the diameter of 0.0312 m.
Explanation:
Given that,
Bulk modulus = 14.0 × 10¹⁰ N/m²
Diameter d = 2.20 m
Depth = 2.40 km
Pressure = ρ g h = 1030 × 9.81 × 2.4 × 1000
= 24.25 × 10⁶ N/m²
Volume = 

Bulk modulus is equal to

now



Δ r = -0.0156 m
change in diameter
Δ d = -2 × 0.0156
Δ d = -0.0312 m
Diameter decreases by the diameter of 0.0312 m.
Answer:C
Explanation:
Mass energy of hydrogen fusing into helium
Would presume you are asked to find the volume, since there is no second volume.
By General Gas Law:
P₁V₁/T₁ = P₂V₂/T₂
1.6 * 168 /255 = 1.3*V₂/285
V₂ = 1.6 * 168 * 285 / (1.3*255)
V₂ = 231.095
Final volume ≈ 231 cm³