(A) We can solve the problem by using Ohm's law, which states:

where
V is the potential difference across the electrical device
I is the current through the device
R is its resistance
For the heater coil in the problem, we know 

 and 

, therefore we can rearrange Ohm's law to find the current through the device:

(B) The resistance of a conductive wire depends on three factors. In fact, it is given by:

where

 is the resistivity of the material of the wire
L is the length of the wire
A is the cross-sectional area of the wire
Basically, we see that the longer the wire, the larger its resistance; and the larger the section of the wire, the smaller its resistance.
 
        
        
        
you could make a self propelled car all you need is cardboard, wheels, and a balloons or rubber bands
  
 
        
             
        
        
        
Answer:
Shown by explanation;
Explanation:
The heat of the sample = mass ×specific heat capacity of the sample × temperature change(∆T)
Assumption;I assume the mass of the samples are : 109g and 192g
∆T= 30.1-21=8.9°c.
The heat of the samples are for 109g are:
0.109 × 4186 × 8.9 =4060.84J
For 0.192g are;
∆T= 67-30.1-=36.9°c
0.192 × 4186×36.9=29656.97J
 
        
             
        
        
        
Your Question:
<span>A
star is born when gas and dust from a nebula become so dense and hot
that nuclear fusion starts. Which of the following forces is responsible
for the formation of a star?
A. 
friction
B. 
gravitation
C. 
magnetism
D. 
electromagnetic energy</span>
Our Teams Answer: B. Gravitation
Our Teams aim's to please and We are happy to help! Its the answer is wrong please notify us quickly for we can fix it quickly! Thanks :)
-ExperimentsDIY
        
                    
             
        
        
        
Answer:
Explanation:
A
35 N  Small Dog <=======BONE=========> Bigger Dog 42 N
B
Fnet = Large Dog - small dog The forces are subtracted because they are acting in opposite Directions.
Fnet = 42 - 35 
Fnet = 7 N
C
m = 2.5 kg
F = 7 N
a = ?
F = m * a
7 = 2.5 a
a = 7 / 2.5
a = 2.8 m/s^2