Answer:
option C (1 and 4)
Explanation:
Like poles repel each other, unlike poles attract each other
P=4800kgm/s
As
p=mΔv
where p is momentum, m is mass and v is velocity
Given values is
m =1200kg
Δv= 17m/s-13m/s=4m/s
Now
p=mΔv
p=(1200kg)*(4m/s)
p=4800kgm/s
Answer: 0.455 m/s^2
Explanation:
f = ma = m x 9.8=689 (the mass is constant)
m = 78.3
now on the elevator
f = 721 = m x a
a= 10.26
the elevator is moving down because there is a increase in weight. the acceleration of elevator = 10.26-9.8 = 0.455
Mass/density= volume so it will be 360/0.9 which equals to 400 and if you want to find mass you just need to multiple volume•density
