Answer:
= 3.87 m/s
Explanation:
Since momentum is conserved, momentum right before and after the boy jumps onto the skateboard should be the same.
Initial momentum = momentum of boy = 43.2 x 4.10 = 177 kg·m/s
Final momentum = momentum of boy and skateboard = (43.2 + 2.50) x v = 45.7v
177 = 45.7v
v = 177 / 45.7 = 3.87 m/s
(Hope this helps can I pls have brainlist (crown)☺️)
Answer:
2.5 m/s
Explanation:
Mechanical energy is the sum of the potential and kinetic energy.
E = PE + KE
E = mgh + ½mv²
172.1 J = (7.26 kg) (9.8 m/s²) (2.1 m) + ½ (7.26 kg) v²
v = 2.5 m/s
Your answer would be D. Mechanical and Pressure/Longitudinal. This is because a sound wave is usually a type of pressure wave caused by the vibration of an object in a conductive medium such as air. These waves are also mechanical because they require a medium to travel through. This is also why sound simply cannot travel through vacuums like space, because they have no mediums in which sound can travel through.
Answer:
18kcal
Explanation:
Melting enthalpy of water: 80 cal/g
The melting enthalpy discribes how much heat is needed to melt a substance. So you get the heat by multiplying the mass of your substance with its melting enthalpy.
225g*18cal/g=18000cal=18kcal
Bruh... but a warm front is different because it brings warm ness and sun, a cold front brings clouds , cloudy weather, and cold weather