Answer:
<h2>
3,343.68kJ </h2>
Explanation:
Heat energy used up can be calculated using the formula:
H = mcΔt
m = mass oof the object (in kg) = 20kg
c = specific heat capacity of water = 4179.6J/kg°C
Δt change in temperature = 80-40 = 40°C
H= 20* 4179.6 * 40
H = 3,343,680Joules
H = 3,343.68kJ
Answer:
1. Attract
2. Repel
3. Attract
4 Repel
always remember when dealing with magnets, Opposites attract
R1 + R4 = 1430 + 1350 = 2780 = R14 series combination of R1 & R4
R2 + R5 = 1350 + 1150 = 2500 = R25
The circuit has been reduced to 3 resistors in parallel
R314 = 2780 * 1100 / (2780 + 1100) = 788 this is the resistance of the parallel combination of R14 and R3
R31425 = 2500 * 788 / (2500 + 788) = 599 which is the equivalent of the circuit - you can also use the formula for 3 resistors in parallel but this seems simpler
Answer:
![a' = 0.35 m/s^2](https://tex.z-dn.net/?f=a%27%20%3D%200.35%20m%2Fs%5E2)
Explanation:
Let say the empty wagon has mass "M"
now by newton's II Law we will have
![F = Ma](https://tex.z-dn.net/?f=F%20%3D%20Ma)
now it is given that empty wagon is pulled with acceleration 1.4 m/s/s
now we will have
![F = 1.4 M](https://tex.z-dn.net/?f=F%20%3D%201.4%20M)
now a child of mass three times the mass of wagon is sitting on the empty wagon
so here we have
![F = (M + 3M) a](https://tex.z-dn.net/?f=F%20%3D%20%28M%20%2B%203M%29%20a)
![1.4 M = 4M a'](https://tex.z-dn.net/?f=1.4%20M%20%3D%204M%20a%27)
so we have
![a' = 0.35 m/s^2](https://tex.z-dn.net/?f=a%27%20%3D%200.35%20m%2Fs%5E2)