Answer:
469.6KJ
Explanation:
Heat energy required can be calculated using the formula
H = mc∆t where
m is the mass of the water
c is the specific heat capacity of the water
∆t is the change in temperature of the water
Given m = 9.78kg
c = 4186j/kg-c.
∆t = 52.07°C - 40.82°C
∆t = 11.25°C
H = 9.78 × 4186 × 11.25
H = 460,564.65Joules
= 460.6KJ
Answer: 50 km, 0, 27.78 m/s
Explanation:
Given
Circumference of the track is 
Speed of car is 
Car drives for 
(a)Distance traveled is

(b)displacement of the car
It can be observed that 12.5 is a multiple of 50, that is, 50 km can be interpreted as 4 complete rounds of the track.
Therefore, the displacement of the car is zero.
(c)To convert kmph to m/s, multiply the entity by 

Answer:
C
Explanation:
a series circuit would be an odd choice to power a battery or light a lamp when a direct would be much more efficient, and it's not converting types of energy, so C is the best possible answer
GPE= height x mass x gravitational field strength
5 x 10 x 9,8=490J
Answer:
Explanation:
r = √(-6.48² + 12.58²) = 14.1508586311... 14.15
θ = arctan(12.58 / -6.48) = 117.25314692... 117.25
(r, θ) = (14.15, 117.25)