Answer:
The one in the middle
Explanation: i listened to the other person and i got it wrong, this is the answer for edge2020 sience review on energy!!!!
trust me its the middle one!!!!!
And everyone if ur not sure, like 100% sure about an answer dont answer at all cuz for 1: ur taking up a spot for others to answer. for 2: you could make people wrong. And for 3: its annoying. And 4: it makes stuff like this happen!
<u>NOT ARGUEING IM JUST PUTTING MY THOUGHTS AND OPINIONS OUT THERE ;)</u><em> many thanks.</em>
Answer:
mu = 0.56
Explanation:
The friction force is calculated by taking into account the deceleration of the car in 25m. This can be calculated by using the following formula:

v: final speed = 0m/s (the car stops)
v_o: initial speed in the interval of interest = 60km/h
= 60(1000m)/(3600s) = 16.66m/s
x: distance = 25m
BY doing a the subject of the formula and replace the values of v, v_o and x you obtain:

with this value of a you calculate the friction force that makes this deceleration over the car. By using the Newton second's Law you obtain:

Furthermore, you use the relation between the friction force and the friction coefficient:

hence, the friction coefficient is 0.56
Since each student emits 100 W, so 170 students will emit:
total heat = 100 W * 170 = 17,000 W
Convert minutes to seconds:
time = 50 min * (60 s / min) = 3000 s
The energy is therefore:
E = 17,000 W * 3000 s
<span>E = 51 x 10^6 J = 51 MJ</span>
Answer with Explanation:
We are given that
Length of wire 1=
Length of wire 2=
Resistivity of copper wire=
Resistivity of aluminum wire=
Wire 1=Copper wire
Wire 2=Aluminum wire
Diameter of both wires are same and resistance of both wires are also same.
We know that
Resistance =
When diameter of wires are same then their cross section area are also same .

When resistance and area are same then the length of wire depend upon the resistivity of wire .
The length of wire is inversely proportional to resistivity.
When resistivity is greater then the length of wire will be short and when the resistivity is small then the length of wire will be large.

Therefore, 
Hence, the length of wire 1 (copper wire) is greater than the length of wire 2 (aluminum).

