Answer:
the answer is the 4th one. the speed of sound is lowest in gas and highest in solid and its because the molecules in solid is closer to each other than the molecules in gas and when the molecules are close to each other, they allow the waves of the sound to travel more quickly.
Answer:
Horizontal distance from the foot of the cliff is 40 m
Explanation:
Given :
Speed of stone 
Vertical distance 
m
Gravitational acceleration 
From the kinematics equation,
Where 
initial velocity ( 
)
So time take to fall down,
sec
Now find horizontal distance travel by stone,
m
Therefore, the horizontal distance travel by stone is 40 m
Answer:
The height will be 917431.2 m.
Explanation:
Power of bulb = 75 W
Time kept on 1 hr = 60 x 60 = 3600 sec
Energy of bulb = power x time
E = 75 x 3600 = 270000 J
From conservation of energy, kinetic energy of the bulb is equal to the potential energy of the bulb due to its height of fall.
Potential energy = m x g x h
Where g = acceleration due to gravity 9.81 m/s2
m = mass = 30 g = 0.03 kg
PE = 0.03 x 9.81 x h = 0.2943h
Equating withe the energy of bulb (still obeying energy conservation)
270000 = 0.2943h
h = 270000/0.2943 = 917431.2 m
Answer:
v = 120 m/s
Explanation:
We are given;
earth's radius; r = 6.37 × 10^(6) m
Angular speed; ω = 2π/(24 × 3600) = 7.27 × 10^(-5) rad/s
Now, we want to find the speed of a point on the earth's surface located at 3/4 of the length of the arc between the equator and the pole, measured from equator.
The angle will be;
θ = ¾ × 90
θ = 67.5
¾ is multiplied by 90° because the angular distance from the pole is 90 degrees.
The speed of a point on the earth's surface located at 3/4 of the length of the arc between the equator and the pole, measured from equator will be:
v = r(cos θ) × ω
v = 6.37 × 10^(6) × cos 67.5 × 7.27 × 10^(-5)
v = 117.22 m/s
Approximation to 2 sig. figures gives;
v = 120 m/s
As you inhale, your ribs move up and out decreasing the internal pressure and increasing the volume of the lungs forcing air into the lungs from an area of externally high pressure in comparison to the low internal pressure.
