180 pounds (lb) converts to 81.647 kilograms (kg).
The answer is 8.
Hope I helped.
Answer:
6.25 m/s
Explanation:
mass of man (m1) = 80 kg
mass of boy (m2) = 20 kg
mass of man and boy after collision (m12)= 20 + 80 = 100 kg
velocity of man and boy after collision (v) = 2.5 m/s
angle θ = 60 °
How fast was the boy moving just before the collision
?
- From the diagram attached, the first image shows the man and the boys motion while the second diagram shows their motion rearranged to form a triangle. With the momentum of the man and the boy forming the sides of the triangle.
- M₁₂ = total momentum after collision = m12 x v = 100 x 2.5 = 250
- Mboy = momentum of the boy before collision = m2 x Velocity of boy
- Mman = momentum of the man before collision = m1 x velocity of man
- from the triangle, cos θ =

cos 60 = 
Mboy = 250 x cos 60 = 125
- recall that momentum of the boy (Mboy) also = m2 x Velocity of boy
therefore
125 = 20 x velocity of boy
velocity of boy = 125 / 20 = 6.25 m/s
To solve this, we simply use trigonometry
the effective value of g along the 45° angle is
g eff = g / sin 45
g eff = g / (√2 / 2)
g eff = 2g / √2
g eff = g √2 ≈ 6.94 m/s²
Answer:
Yes you can. The charging current will be the lowest of the two current ratings of device and charger. The charger and the phone have complex internal circuitry that enable this behaviour.
But using a weaker charger for your phone will only lengthen charging time. And using a stronger charger than that the phone will accept doesn't affect charging at all and only wastes money.