Answer:
<em>765,000Joules or 765kJ</em>
Explanation:
The Quantity of heat required is expressed as;
Q = (mcΔt)al + (mcΔt)water
m is the mass
c is specific heat capacity
Δt is the change in temperature
Q = (3(900)(90-5)) + (1.5(4200)(90-5))
Q = 2700*85 + 6300*85
Q = (2700+6300)85
Q = 9000*85
<em>Q = 765,000</em>
<em>Hence the amount of energy needed is 765,000Joules or 765kJ</em>
Batteries supply electrons to the circuit by releasing negatively charged atoms or ions. These ions are produced by the batteries through a chemical reaction that spontaneously occurs within the battery. So the negative end of the battery pushes the ions towards the positive end of the circuit with the help of the voltage. This is why eventually, batteries "run out" when the electrode is used up and the chemical reaction can no longer continue.
Answer:
The velocity of the man from the frame of reference of a stationary observer is, V₂ = 5 m/s
Explanation:
Given,
Your velocity, V₁ = 2 m/
The velocity of the person, V₂ =?
The velocity of the person relative to you, V₂₁ = 3 m/s
According to the relative velocity of two
V₂₁ = V₂ -V₁
∴ V₂ = V₂₁ + V₁
On substitution
V₂ = 3 + 2
= 5 m/s
Hence, the velocity of the man from the frame of reference of a stationary observe is, V₂ = 5 m/s
Answer 1) : 62.5 km/hour is the average velocity of the train.
2) The final velocity of the car at the end of 75 m is 14.69 m/s
Explanation:
1) Displacement of the train = 100 km + 150 km = 250 km
Total time train took =1 hour 15 min+ 45 min + 2 hours = 240 min = 4 hours
Average velocity=
62.5 km/hour is the average velocity of the train.
2) The acceleration of the car, a= 1.2 
Distance covered by the car,s = 75 m
Initial velocity of the car ,
= 6 m/s
Final velocity of thre car ,
=?
Using third equation of motion:


The final velocity of the car at the end of 75 m is 14.69 m/s
Answer:
C = 17 i^ - 7 j^ + 16 k^
, | C| = 24.37
Explanation:
To work the vactor component method, we add the sum in each axis
C = A + B = (Aₓ + Bₓ) i ^ + (
+
) i ^ + (
+
) k ^
Cₓ = 12+ 5 = 17
= -37 +30 = -7
= 58 -42 = 16
Resulting vector
C = 17 i ^ - 7j ^ + 16k ^
The mangitude of the vector is
| C | = √ c²
| C | = √( 17² + 7² + 16²)
| C| = 24.37