Answer:
0.853 m/s
Explanation:
Total energy stored in the spring = Total kinetic energy of the masses.
1/2ke² = 1/2m'v².................... Equation 1
Where k = spring constant of the spring, e = extension, m' = total mass, v = speed of the masses.
make v the subject of the equation,
v = e[√(k/m')].................... Equation 2
Given: e = 39 cm = 0.39 m, m' = 0.4+0.4 = 0.8 kg, k = 1.75 N/cm = 175 N/m.
Substitute into equation 2
v = 0.39[√(1.75/0.8)
v = 0.39[2.1875]
v = 0.853 m/s
Hence the speed of each mass = 0.853 m/s
Explanation:
VELOCITY: BECAUSE ITS A VECTOR QUANTITY
Answer:
is the distance from the obstacle of reflection.
wavelength 
Explanation:
Given that:
- frequency of sound,
- time taken for the echo to be heard,
- speed of sound,
We know,
<em>During an echo the sound travels the same distance back and forth.</em>
is the distance from the obstacle of reflection.
<u>Now the wavelength of sound waves:</u>
Answer:
1.23 m/s
Explanation:
The kinetic energy of the sprinter is:
KE = 0.5 * m(s) * v²
KE = 0.5 * 77 * 7.5²
KE = 2165.63 J
If the KE of the sprinter and the KE of the elephant are equal, hence:
2165.63 = 0.5 * m(e) * v²
2165.63 = 0.5 * 2850 * v²
=> v² = 1.52
v = √(1.52)
v = 1.23 m/s
