Newton's first law of motion is that an object in motion will tend to stay in motion unless an external force acts upon it.
Answer:
Explanation:
For calculating resistance of a conductor , the formula is
R = ρ l / A , ρ is specific resistance , l is length and A is cross sectional area of wire.
For first wire length is l₁ , area is A₁ resistance is R₁, for second resistance is R₂ , length is l₂ and area is A₂
Given , l₁ = 2l₂ , A₁ = 4A₂ , area is proportional to square of thickness.
R₁ / R₂ = I₁A₂ / I₂A₁
= 2l₂ x A₁ / 4 I₂A₁
= 1 / 2
2R₁ = R₂
Power = V² / R
Ratio of power = (V² / R₁) x (R₂ / V²)
= R₂ / R₁
= 2 .
The increase in temperature of the metal hammer is 0.028 ⁰C.
The given parameters:
- <em>mass of the metal hammer, m = 1.0 kg</em>
- <em>speed of the hammer, v = 5.0 m/s</em>
- <em>specific heat capacity of iron, 450 J/kg⁰C</em>
The increase in temperature of the metal hammer is calculated as follows;
where;
<em>c is the </em><em>specific heat capacity</em><em> of the metal hammer</em>
<em />
Assuming the metal hammer is iron, c = 450 J/kg⁰C
Thus, the increase in temperature of the metal hammer is 0.028 ⁰C.
Learn more about heat capacity here: brainly.com/question/16559442
Your position in meters will, measured relative to the starting point of the car behind you, be
x1(t) = 10 + 23.61 t - 1/2 4.2 t^2
his position will be
x2(t) = 16.67 t
Hence at any time the separation s(t) will be
s(t) = x1(t) - x2(t) = 10 + 6.94 t -2.1 t^2
Now I assume you mean that you will decelerate UNTIl you are driving at the legal speed limit (60 km/h). That will take you:
16.67 m/s = 23.61m/s - 4.2 m/s^2 * t
t = 1.65 seconds
What is the separation at that time? If it is still greater than zero, there will be no collision:
s(1.65) = 10 + 6.94 *1.65 -2.1 (1.65)^2 = 15.73 meters.
Hence you will NOT collide. The 1.65 s you calculated was the time needed to brake to the speed of 60 km/h.
