Answer:
7.35m/s²
Explanation:
From the question we are not told what to find but we can as well find the acceleration of the wagon.
According to newton second law of motion

Fm is the moving force = 410N
is the coefficient of friction = 0.18
m is the mass = 45kg
g is the acceleration dur to gravity = 9.8m/s²
a is the acceleration of the wagon
Substitute the given data into the equation ang get ax

Hence the acceleration of the wagon is 7.35m/s²
Answer : The change in enthalpy of the reaction is, -310 kJ
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
The given main reaction is,

The intermediate balanced chemical reaction will be,
(1)

(2)

(3)

Now we will reverse the reaction 1 and multiply reaction 1 by 2, reaction 2 by 2 and reaction 3 by 3 then adding all the equations, we get :
(1)

(2)

(3)

The expression for enthalpy of formation of
will be,



Therefore, the change in enthalpy of the reaction is, -310 kJ
Answer:
-
Explanation:
We are given that
Mass of cars= m=1900 kg
Initial speed of car=u=20 m/s
Final speed of car=v=0
Time=
=1.3 s
We have to find the average force exerted on the car.
Average force=



Hence, the average force exerted on the car that hits a line of water barrels=-
Answer:
A
Explanation:
the metal lunchbox has a higher conductivity
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Explanation:
Geocentric model said that the Earth is at the center of the universe and everything revolves around it. It was considered to be stationary. Galileo proved this model incorrect with the help of his astronomical observations. Some of the key observation that he used to support the heliocentric model were:
1. He proposed the theory that the tides on the Earth occur because of its motion.
2. He observed the phases of the Venus which meant that the Venus revolved around the Sun and not the Earth.
3. He observed other planets and thus noted that they also move around the Sun and not Earth.
4. He discovered the Moons of other planets.