We have to covert 512 cal of heat in kilo joules.
As, 1 cal = 0.004184 kJ = 4.184 joules.
Therefore,

Thus, combustion of a small wooden match produces approximately ( in kilo joules ) is 2.142 kJ .
Answer:
Explanation:
7a) t = d/v = 100/45cos14.5 = 2.29533...= 2.30 s
7b) h = ½(9.81)(2.29533/2)² = 6.46056... = 6.45 m
or
h = (45sin14.5)² / (2(9.81)) = 6.47 m
which rounds to the same 6.5 m when limiting to the two significant digits of the initial velocity.
Answer:
The magnitude of the force is 34.59 N.
Explanation:
Given that,
Inside pressure 
Area 
Outside pressure = 1 atm
We need to calculate the magnitude of the force
Using formula of force


Where,
=inside Pressure
=outside Pressure
A = area
Put the value into the formula


Hence, The magnitude of the force is 34.59 N.
Answer:
Option B, Some of the cars' kinetic energy was converted to sound and heat energy.
Explanation:
In an elastic collision, no energy is lost during and after collision. Thus, it can be said that in an elastic collision both momentum and kinetic energy remains conserved.
While in non-elastic collision, kinetic energy of the system is lost. However, the momentum of the system is conserved. Generally, during and after collision some of the kinetic energy is lost as thermal energy, sound energy etc.
Hence, option B is correct