We first calculate the friction on the sled using:
F = ma
a = 20 / 22
a = 0.91 m/s²
Now we use the formula:
2as = v² - u²
v = √(2as + u²)
v = √[2(0.91)(5.2) + 0]
v = 3.08 m/s
Answer:
400 N
Explanation:
From the question,
F = kmm'/r²........................ Equation 1
Where F = gravitation force, m and m' = mass 1 and mass 2 respectively, r = distance between the masses.
Given; F = 800 N
Substitute these values into equation 1
800 = kmm'/r².............. Equation 2
If the distance is doubled (2r), and one of the mass is doubled (2m), The new force is
F' = k(2m)(m')/(2r)²
F' = 2kmm'/4r²
F' = kmm'/2r²................. Equation 3
Comparing equation 2 and equation 3
F' = F/2............................ Equation 4
Substitute the value of F into equation 4
F' = 800/2
F' = 400 N
Answer:
A. Endothermic reaction.
B. +150KJ.
C. 250KJ.
Explanation:
A. The graph represents endothermic reaction because the heat of the product is higher than the heat of the reactant.
B. Determination of the enthalpy change, ΔH for the reaction. This can be obtained as follow:
Heat of reactant (Hr) = 50KJ
Heat of product (Hp) = 200KJ
Enthalphy change (ΔH) =..?
Enthalphy change = Heat of product – Heat of reactant.
ΔH = Hp – Hr
ΔH = 200 – 50
ΔH = +150KJ
Therefore, the enthalphy change for the reaction is +150KJ
C. The activation energy for the reaction is the energy at the peak of the diagram.
From the diagram, the activation energy is 250KJ.