Density = Mass/Volume
So, given mass = 20 g and volume = 40 cm^3
By substituting in above equation, Density = 20/40 = 0.5 g/cm^3
Hope it helps.
Answer:
The change in velocity is 15.83 [m/s]
Explanation:
Using the Newton's second law we have:
ΣF = m*a
The force in the graph is 185 N, therefore:
![185=0.369*a\\Where\\a=acceleration made it by the force [m/s^2]](https://tex.z-dn.net/?f=185%3D0.369%2Aa%5C%5CWhere%5C%5Ca%3Dacceleration%20made%20it%20by%20the%20force%20%5Bm%2Fs%5E2%5D)
![a=501.35[m/s^2]](https://tex.z-dn.net/?f=a%3D501.35%5Bm%2Fs%5E2%5D)
Now using the following kinematic equation:
![V^{2}=Vi^{2} + 2*a*(x-xi) \\where\\V=final velocity [m/s]\\Vi= initial velocity [m/s] = 0 the hockey disk is in rest when receives the hit.\\ x = Final position [m] = 0.4 m\\xi = initial position [m] = 0.15m\\](https://tex.z-dn.net/?f=V%5E%7B2%7D%3DVi%5E%7B2%7D%20%2B%202%2Aa%2A%28x-xi%29%20%5C%5Cwhere%5C%5CV%3Dfinal%20velocity%20%5Bm%2Fs%5D%5C%5CVi%3D%20initial%20velocity%20%5Bm%2Fs%5D%20%3D%200%20the%20hockey%20disk%20is%20in%20rest%20when%20receives%20the%20hit.%5C%5C%20x%20%3D%20Final%20position%20%5Bm%5D%20%3D%200.4%20m%5C%5Cxi%20%3D%20initial%20position%20%5Bm%5D%20%3D%200.15m%5C%5C)
Now replacing the values:
![V^{2}=0 + 2*501.35*(0.4-0.15)\\ \\V= 15.83[m/s]](https://tex.z-dn.net/?f=V%5E%7B2%7D%3D0%20%2B%202%2A501.35%2A%280.4-0.15%29%5C%5C%20%5C%5CV%3D%2015.83%5Bm%2Fs%5D)
Answer:
The potential energy of the ball is 784 joules. And the kinetic energy of it is 392 while falling halfway down.
Explanation:
PE = mass (2kg) * Gravitational acceleration (9.8 m/s^2)* height (40 meters)
KE = 1/2 mass (1 kg) * velocity^2 (19.8)
Answer:
All the given option is false.
Explanation:
A)
This is not true for all the materials like composite because the Poisson ratio for composite material can be negative that is why positive tensile stress may produce positive lateral strain.
B)
This is not true for all the material because the Poisson ratio for some material can be positive that is why positive tensile stress may produce negative lateral strain.
C)
The explanation is same as option A.
D)
This is not true for all the materials ,It is valid only up to elastic limit .After the elastic limit the strain and stress does not follow linear path.
E)
This is not true for all the materials because some materials like composite is having negative value of Young's modulus.
Therefore all the given option is false.
