nuclear energy is found in the nucleus of an atom
thermal energy is found when internal energy is transferred
Electrical energy is found in the flow of electrical charges
Chemical energy is found in the bonds between atoms
The centripetal force is the gravitational force of attraction between the Earth and the Moon.
Also, the gravitational force of attraction between the Earth and the Sun is the centripetal force that causes the Earth to stay in orbit around the Sun.
Also, the gravitational force of attraction between a TV satellite, a weather satellite, or a GPS satellite and the Earth is the centripetal force that causes each satellite to stay in orbit around the Earth.
Answer:
(B) The balls reach the ground at the same instant.
Explanation:
Since it is a projectile motion, the time required to reach the ground is given by
t = √2h/g
Where h is the height from which the balls are thrown and g is the acceleration due to gravity.
Since both of the balls were thrown from the same height and the acceleration of both balls are also same they will reach the ground at the same instant.
Answer:
The reading of the experiment made in air is 50 g more than the reading of the measurement made in water.
Explanation:
Knowing that the density of lead is
and the volume, we can calculate the true weight of the piece of lead:
![weight_{lead}=\rho _{lead}*V_{lead}=11,3 g/cm^{3} *50 cm^{3} = 565 g](https://tex.z-dn.net/?f=weight_%7Blead%7D%3D%5Crho%20_%7Blead%7D%2AV_%7Blead%7D%3D11%2C3%20%20g%2Fcm%5E%7B3%7D%20%2A50%20cm%5E%7B3%7D%20%20%20%3D%20565%20g)
When the experiment is done in air, we can discard buoyancy force (due to different densities) made by air because it's negligible and the measured weight is approximately the same as the true weight.
When it is done in water, the effect of buoyancy force (force made by the displaced water) is no longer negligible, so we have to take it into account.
Knowing that the density of water is 1 g per cubic centimeter, and that the volume displaced is equal to the piece of lead (because of its much higher density, the piece of lead sinks), we can know that the buoyancy force made by water is 50 g, opposite to the weight of the lead.
![Weight_{measured}=weight_{lead}-weight_{water}=\frac{(565 g *9.8 m/s^{2} -50 g*9.8 m/s^{2})}{9,8m/s^{2} } = 515 g](https://tex.z-dn.net/?f=Weight_%7Bmeasured%7D%3Dweight_%7Blead%7D-weight_%7Bwater%7D%3D%5Cfrac%7B%28565%20g%20%2A9.8%20m%2Fs%5E%7B2%7D%20%20-50%20g%2A9.8%20m%2Fs%5E%7B2%7D%29%7D%7B9%2C8m%2Fs%5E%7B2%7D%20%7D%20%20%3D%20515%20g)
Now that we have the two measurements, we can calculate the difference:
![Difference= |Weight _{in water}- Weight _{in air}|=|515 g-565 g|=50 g](https://tex.z-dn.net/?f=Difference%3D%20%7CWeight%20_%7Bin%20%20%20water%7D-%20Weight%20_%7Bin%20%20%20air%7D%7C%3D%7C515%20g-565%20g%7C%3D50%20g)
The reading of the experiment made in air is 50 g more than the reading of the measurement made in water.