Calculate the power of a man of mass 50 kg if he can climb a staircase of height 3m in 10 seconds ​

Explanation:

Mass of man = 50kg

Height of ladder, h2 = 10m

(i) Work done by man =

mgh2 = 50 × 9.8 × 10 = 4900J

(ii) increase in his potential energy:

Height,h2 = 10m

Reference point is ground, h1 = 0m Gravitational potential energy = Mg (h2-h1)

= 50 × 9.8 × (10-0)

= 50 × 9.8 × 10 = 4900J

the chart show the masses and velocities of two colliding objects that stick together after a collision.

according to the law of conservation of momentum, the momentum of the object after the collision is  

answer

1,500

kg • m/s.

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