Answer:
120s^-1
Explanation:
v=12v
I=10A
and since rate is with time, therefore rate=energy/time.
H=IV
10×12=120/s
therefore the rate is 120s^-1
A) To calculate the charge of each coin, we must apply the expression of the Coulomb's Law:
F=K(q1xq2)/r²
F: The magnitud of the force between the charges. (F=2.0 N).
K: Constant of proporcionality of the Coulomb's Law (K=9x10^9 Nxm²/C²).
q1 and q2: Electrical charges.
r: The distance between the charges (r=1.35 m).
We have the values of F, K and r, so we can calculate q1xq2, because both<span> coins have identical charges:
</span>
q1xq2=(r²xF)/K
q1xq2=(1.35 m)²(2.0 N)/9x10^9 Nxm²/C²
q1xq2=3x10^-10 C
q1=q2=(<span>3x10^-10 C)/2
</span>Then, the charge of each coin, is:
<span>
q1=1.5x</span><span>10^-10 C
</span>q2=1.5x10^-10 C
B) <span>Would the force be classified as a force of attraction or repulsion?
</span>
It is a force of repulsion, because both coins have identical charges and both are postive. In others words, when two bodies have identical charges (positive charges or negative charges), the force is of repulsion.
Answer: The magnitude of the velocity = 2/5 m/s
Explanation:
In this question, the magnitude of the velocity is the product of the magnitude of the displacement vector and the magnitude of the component of the velocity that acts in the direction of displacement.
This will be a scalar projection of V onto X
Please find the attached files for the solution
Here is your answer

REASON :
We know that
Potential difference, V= W/q
where, W is work done
and, q is magnitude of charge
Given,
V= 9.0 v and W= 45 J
So,
using above relation, we get
9= 45/q
q= 45/9
q= 5 coulomb
HOPE IT IS USEFUL
Density formula is:
D = m / V
Volume of the matchbox car:
V = 46 ml - 41 ml = 5 ml = 0.005 l = 0.005 dm³
D = 10 g / 0.005 dm³
D = 2000 g / dm³ = 2 kg / dm³ = 2 × 10 ^(-3) kg/m³