Answer :
Final answer:
To calculate the loss of potential energy for the falling shell, use the formula PE_loss = PE_initial - PE_final.The option (a) is correct.
Explanation:
The loss of potential energy (PE) as a 50.0 kg shell fell from a maximum height of 400 m to a height of 100. m can be calculated as follows:Initial potential energy: PE_initial = mgh_initial.Final potential energy: PE_final = mgh_finalLoss of potential energy: PE_loss = PE_initial - PE_final,Substitute the given values to find the loss of potential energy. ΔPE is the change in potential energy,mm is the mass of the object,gg is the acceleration due to gravity (approximately 9.8 m/s29.8m/s2 on the surface of the Earth) ΔhΔh is the change in height. In this case, the object is a 50.0 kg shell falling from a maximum height of 400 m to a height of 100 m.ΔPE=50.0 kg⋅9.8 m/s2⋅(100 m−400 m)ΔPE=50.0kg⋅9.8m/s2⋅(100m−400m)
ΔPE=50.0 kg⋅9.8 m/s2⋅(−300 m)ΔPE=50.0kg⋅9.8m/s2⋅(−300m),ΔPE=−147,000 JΔPE=−147,000J The negative sign indicates that the potential energy is decreasing as the object falls.Therefore, the correct answer is:147,000 J. Potential energy (PE) is equal to the mass (m) of the object times acceleration due to gravity (g) times the height (h) of the object. The potential energy of this rock is 12 kJ (a kilojoule, kJ, is equal to 1000 joules).
Potential Energy : (P.E. or U) “The energy possessed by a bo tody due its position above the ground . or change in state.” UNIT : Unit of P.E. = S.I. UNIT OF ENERGY = Joule (J). The formula for potential energy depends on the force acting on the two objects. For the gravitational force the formula is P.E. = mgh, where m is the mass in kilograms, g is the acceleration due to gravity (9.8 m / s2 at the surface of the earth) and h is the height in meters.
