Explanation:
Mass of boy = 40 kg
Mass of box = 20 kg
Total mass = 60 kg
Initial potential energy = 0 (since height would be 0 initially)
Final potential energy = mgh
Taking g as 10 m/s²,
=> 60 × 10 × 15
= 9,000 J
So, work done = final potential energy - initial potential energy
= 9,000 J
Power = Work/Time
=> Power = 9000/25
=> Power = 360 J/s
or 360 watt.
First ones 40 and I’m not sure bout the second one but through process of elimination either always or never cause nothing in math is uncertain or non existent
Answer: 2605 more on weekdays
Step-by-step explanation:
14239 - 11634 = 2605
Step-by-step explanation:
here,,
a=3,b=10,C=120°
c^2=a^2+b^2-2ab cos120°
=(3)^2 +(10)^2 _2 (3)(10)(-1/2) [cos120°=-1/2]
=9+100-(-30)
=109+30
=139
c=(139 )1/2=11.79
c=12