This problem is a comparison of how fast sound travels through different mediums. <span>The speed of sound in iron is 5950 m/s while in air, it is 331 m/s. Given that the train is 100km away, we can use the given values to solve for the missing values:
</span>
Listening through air:
100000/331 = 302 seconds
Listening through the rails:
100000/5950 = 16.81 seconds
Answer:
a) E = 6.4 1019 J b) v = 0.69 10⁴4 m / s
Explication
a) convert E = 4.0 eV
1 eV = 1.6 10⁻¹⁹ J
E = 4.0 eV (1.6 10⁻¹⁹ J / 1 eV)
E = 6.4 10⁻¹⁹ J
b) Suppose we have a frontal shock and all the kinetic energy of oxygen is transferred to Cs
Ei = K = ½ m v²
Ef = 6.4 10⁻¹⁹ J
½ m v² = 6.4 10⁻¹⁹
The oxygen mass of the periodic table is
PA = 15,999 u
1u = 1.660 10⁻²⁷ kg
Pa = 15,999 1,660 10⁻²⁷ kg
m= Pa = 26,558 10⁻²⁷ kg
Let's calculate the speed
v2 = 2 / m 6.4 10⁻¹⁹
v2 = 2 / 26,558 10⁻²⁷ 6.4 10⁻¹⁹ =
v = √0.4819 10⁸
v = 0.69 10⁴4 m / s
Answer:
Explanation:
The electric potential can be found by using the following formula
Applying this formula to each charge gives the total potential.
Since the potential is a scalar quantity, it is safe to sum all the potentials straightforward. And since they all placed on the corners of a square, +3 and -3 μC charges cancel out each other.
Answer: 5.5 m/s
Explanation:
As we are told the runner accelerates at a constant rate, we can use the following equation:
Where:
is the runner's final velocity
is the runner's initial velocity
is the runner's constant acceleration
is the time it takes the runner to reach the final velocity
Finally: