Answer:
D. 2.8 × 10⁹ N
Explanation:
The force between two charges is directly proportional to the amount of charges at the two points and inversely proportional to the square of distance between the two points.
Fe= k Q₁Q₂/r²
Q₁= -0.0045 C
Q₂= -0.0025 C
r= 0.0060 m
k= 9.00 × 10 ⁹ Nm²/C²
Fe= (9.00 × 10 ⁹ Nm²/C²×-0.0045 C×-0.0025 C)/0.0060²
=2.8 × 10⁹ N
Answer:
45.3°C
Explanation:
Heat gained = mass × specific heat × increase in temperature
q = mC (T − T₀)
Given C = 0.128 J/g/°C, m = 94.0 g, q = 305 J, and T₀ = 20.0°C:
305 J = (94.0 g) (0.128 J/g/°C) (T − 20.0°C)
T = 45.3°C
Answer:
Mass of car = 1098 kg
Explanation:
Here law of conservation of momentum is applied.
Let mass of car be m.
Initial momentum = Final momentum.
Initial momentum = 4350 x 7.39 + m x 0 = 32416.5 kgm/s
Final momentum = 4350 x 4.55 + m x 11.5 = 19792.5+11.5m
We have
19792.5+11.5m = 32416.5
m = 1097.97 kg
Mass of car = 1098 kg
Answer:
I = 18 x 10⁻⁹ A = 18 nA
Explanation:
The current is defined as the flow of charge per unit time. Therefore,
I = q/t
where,
I = Average Current passing through nerve cell
q = Total flow of charges through nerve cell
t = time period of flow of charges
Here, in our case:
I = ?
q = (9 pC)(1 x 10⁻¹² C/1 pC) = 9 x 10⁻¹² C
t = (0.5 ms)(1 x 10⁻³ s/1 ms) = 5 x 10⁻⁴ s
Therefore,
I = (9 x 10⁻¹² C)/(5 x 10⁻⁴ s)
<u>I = 18 x 10⁻⁹ A = 18 nA</u>