Answer:
We know that potential energy of a body;
= mass(m)× gravitational acceleration(g) × height(h)
Lets find out the mass of the body
P.E. = mgh
=> 6500J = mass × 9.8m/s^2 × 12m
=>6500J = mass × ( 9.8 × 12 ) × ( m/s^2 × m)
=> 6500 Nm = m × 117.6 × m^2 / s^2
=> 6500/117.6 Ns^2/m = mass [°.° Ns^2/m = kg]
=> 55.272 Kg = mass
Therefore the mass of the body = 55.272 kg ~ <em>6</em><em>0</em><em> </em><em>k</em><em>g</em><em> </em>(Ans)
Hope it helps you
Answer:
C
Explanation:
Lifting heavy weights every day
Answer:
57 kg
Explanation:
Mass of seesaw = 20 kg
Length of seesaw = 4 m
Mass of child on the longer end = 30 kg
The weight of the seesaw acts at the center i.e. 2m
The algebraic sum of moments of all forces about any point is zero, hence, using the fulcrum as the reference point:
[x * 9.8* 1.5] - [20 * 9.8* (2.5 - 2)] - [30 * 9.8 * 2.5] = 0
=> 14.7x = (20*9.8*0.5) + 735
14.7x = 98 + 735
14.7x = 833
=> x = 833/14.7
x = 57 kg
Let the moving object be object 1 and the stationary object be object 2.
Momentum of object 1 before collision = 55 kg*m/s
Momentum of object 2 before collision = 0 kg*m/s
Momentum of object 1 after collision = 13 kg*m/s
According to the law of conservation of momentum, the sum of the momenta of 2 objects remains the same even after collision. So,
Momentum of object 1 before collision + momentum of object 2 before collision = Momentum of object 1 after collision + momentum of object 2 after collision
55 + 0 = 13 + momentum of object 2 after collision
Momentum of object 2 after collision = 55 - 13 = 42 kg*m/s
Hope I helped!