Answer:
0.22 m
Explanation:
We are told that the driver can survive an acceleration of 50g only if the collision lasts no longer than 30 ms. So,
The acceleration is
where the negative sign is due to the fact that this is a deceleration, since the driver comes to a stop in the collision.
First of all, we can find what the initial velocity of the car should be in this conditions by using the equation:
And since the final velocity is zero, v=0, and solving for u,
And now we can find the corresponding distance travelled using the equation:
Answer:
by using formula F=ma which is m stand for mass a stand for acceleration. so 500kg × 2 ms^-2
Answer:
The wife have to sit at 0.46 L from the middle point of the seesaw.
Explanation:
We need to make a sketch of the seesaw and the loads acting over it.
And by the studying of the Newton's law we can find the equation useful to find the distance of the mother sitting on the seesaw with respect to the center ot the pivot point.
A logical intuition will give us the idea that the mother will be on the side of her son to make the balance.
The maximum momentum with respect to the pivot point (0) will be:
Where L/2 is the half of the distance of the seesaw
Therefore the other loads ( mom + son) must be create a momentum equal to the maximum momentum.
Answer:
3.1×10⁻¹¹ N
Explanation:
Use Coulomb's law:
F = k q₁ q₂ / r²
F = (9×10⁹) (6.0×10⁻¹⁰) (2.3×10⁻¹⁵) / (0.02 m)²
F = 3.1×10⁻¹¹
Answer:
The correct answer would be B. 18 to 26%.
The muscle efficiency is calculated by dividing mechanical work output by total metabolic cost.
It is estimated that human muscles have an efficiency of about 18% to 26%.
The efficiency is low because most of the energy is lost when food energy is converted into ATP (adenosine triphophate).
In addition, there is second energy loss when energy in the form of ATP is converted into the mechanical energy such as rowing, cycling et cetera.
