Answer:
Q (reaction) = -69.7 kJ
Explanation:
Octane reacts with oxygen to give carbon dioxide and water.
C₈H₁₈ + 25 O₂ ---> 16 CO₂ +18 H₂O
This reaction is exothermic in nature. Therefore, the energy is released into the atmosphere. This reaction took place in a calorimeter, there the temperature (T) increases by 10 C. The heat capacity of the calorimeter is 6.97 kJ/C
The heat (q) of the reaction is calculated as follows:
Q= -cT, where c is the heat capacity of the calorimeter and T is the increase in temperature
q = -(6.97) x (10) = -69.7kJ
<em>Since the heat capacity is given in kilo -joule per degree Celsius, therefore, the mass of octane is not required </em>
Answer:
87.1 mph
Explanation:
We are given that
Mass,m=60 kg
Power,P=340 W
Speed,v=5 m/s
Area,
Drag coefficient,
Coefficient of rolling resistance,
Friction force,
Where 
Let speed of cyclist=v'
Drag force,
Density of air,
Power,P=
1 m=0.00062137 miles
1 hour=3600 s
Answer:
Doubling the voltage in this arrangement both doubles the voltage drop across the resistor and the current through it. The bulb will be much brighter.
Answer:
D
Explanation:
The friction force is the weight force times the coefficient of friction. So diving by the coefficient gives you the weight force which is equivalent to the normal force.
