Explanation:
In physical sciences, mechanical energy is the sum of potential energy and kinetic energy. It is the macroscopic energy associated with a system. The principle of conservation of mechanical energy states that if an isolated system is subject only to conservative forces, then the mechanical energy is constant. If an object moves in the opposite direction of a conservative net force, the potential energy will increase; and if the speed (not the velocity) of the object changes, the kinetic energy of the object also changes. In all real systems, however, nonconservative forces, such as frictional forces, will be present, but if they are of negligible magnitude, the mechanical energy changes little and its conservation is a useful approximation. In elastic collisions, the kinetic energy is conserved, but in inelastic collisions some mechanical energy may be converted into thermal energy. The equivalence between lost mechanical energy (dissipation) and an increase in temperature was discovered by James Prescott Joule.
Answer:
20 Hz, 20000 Hz
0.0166 m, 16.6 m
Explanation:
The minimum frequency that a human ear can hear is 20 Hz
The maximum frequency that a human ear can hear is 20000 Hz.
v = Velocity of sound = 332 m/s
Wavelength is given by
The longest wavelength that can be heard by the human ear is 16.6 m
The shortest wavelength that can be heard by the human ear is 0.0166 m.
Answer:
mantle
Explanation:
Below the crust lies a layer of very hot, almost solid rock called the mantle. Beneath the mantle lies the core. The outer core is a liquid mix of iron and nickel, but the inner core is solid metal. Sometimes, hot molten rock, called magma, bursts through Earth's surface in the form of a volcano.
Answer:
4.5g/cm^3
Explanation:
Here, Mass(m)=67.5g
Volume(v)=15cm^3
Now, According to formula,
Density(p)=m/v
=67.5/15
=4.5g/cm^3
d=vi*t+(1/2)gt²
d=11 m
g=9.8 m/s²
vi=0 m/s
11 m=0 m/s*t+(1/2)9.8 m/s²t²
11 m=4.9 m/s²t²
t²=11 m / 4.9 m/s²
t=√(11 m / 4.9 m/s²)=1.489... s≈1.5 s
Answer: the time the sone is in flight is 1.5 s
