Answer:
(a) 2.5 m/s
(b) 37.5 KJ
Explanation:
(a)
From the law of conservation of momentum, Initial momentum=Final momentum
and making 
the subject then
and since 
is initial velocity of car, value given as 4 m/s, 
is the initial velocity of the three cars stuck together, value given as 2 m/s and 
is the final velocity which is unknown. By substitution
(b)
Initial kinetic energy is given by
Final kinetic energy is given by
The energy lost is given by subtracting the final kinetic energy from the initial kinetic energy hence
Energy lost=350-312.5=37.5 KJ
S: 198 m
v=39 m/s
u=0
t=?
a=?
v²=u²+2as
(39)²=(0)²+2(a)(198)
1521=396a
1521/396=a
3.84 m/s^2 = a
Hope I helped :)
I would assume that the magnesium would have to come into contact with an ion in order to become a magnesium ion.
Answer:
The metal will melt but their will be no change in temperature.
Explanation:
The metal is at its melting temperature which means it is still in solid phase but have to cross the enthalpy of its condensation at this same temperature to convert into liquid phase.
<u>On supplying heat, the metal's temperature will not change as the heat will be required as enthalpy of condensation to melt the solid to liquid at the melting temperature.</u>
