Answer:
The change in momentum = -20000 kg m/s.
Explanation:
Mass m = 1000 kg
speed v₁ = 20 m/s
speed v₂ = 0 m/s
We know that,
The change in momentum
ΔP = m (Δv)
ΔP = m (v₂ - v₁)
      = 1000 (0 - 20)
      = 1000 (-20)
      = -20000 kg m/s
Thus, the change in momentum = -20000 kg m/s.
Note: negative sign indicates that the velocity is reducing when it hits the barrier.
 
        
             
        
        
        
Answer:
temperature measures heat - the unit is Celsius - and it is measured with a thermometer. 
length is measuring how long, tall, or wide something is  - the base unit it metres - and it is measured with a ruler or a metre stick
volume is measuring the quantity of a three dimensional space - the unit is cubic centimetre - you find volume by taking the measurements with a ruler 
mass is measuring how much space something takes up/ weight - unit is the gram - you use a scale
 
        
             
        
        
        
Answer:
Copper
Explanation:
Capacitance is directly proportional to dielectric constant
Aluminium and zinc are highly reactive and have high dielectric contact.
Copper has less dielectric constant hence capacitance will decrease 
 
        
             
        
        
        
Answer:
no one ever amswers my questions