SCIENCE
PHYSICAL SCIENCES
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
w=mg
|
|
w=m/g
|
|
w=g/m
|
|
w=g + m
|
Detailed explanation-1: -Let us calculate the work done in lifting an object of mass m through a height h, such as in Figure 1. If the object is lifted straight up at constant speed, then the force needed to lift it is equal to its weight mg. The work done on the mass is then W = Fd = mgh.
Detailed explanation-2: -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.
Detailed explanation-3: -Updated On: 27-06-2022. Both sides are dimensionally the same, hence the equations 12mv2 = mgh is dimensionally correct. Step by step solution by experts to help you in doubt clearance & scoring excellent marks in exams.
Detailed explanation-4: -To express this concept mathematically, the work W is equal to the force f times the distance d, or W = fd. If the force is being exerted at an angle to the displacement, the work done is W = fd cos .
Detailed explanation-5: -mgh=12mv2, where letters have their usual meanings. Hint: The dimensions of physical quantities are the powers to which the fundamental quantities are raised to represent that quantity. All physical quantities can be expressed as a combination of seven fundamental or base quantities.