Answer:
A. It is always a positive force
Explanation:
Hooke's law describes the relation between an applied force and extension ability of an elastic material. The law states that provided the elastic limit, e, of a material is not exceeded, the force, F, applied is proportional to the extension, x, provided temperature is constant.
i.e F = - kx
where k is the constant of proportionality, and the minus sign implies that the force is a restoring force.
The applied force can either be compressing or stretching force.
The victim's head is accelerated faster and harder than the
torso when the victom is involved in a typical rear-end collision.
The traffic accident where a vehicle crashes into another
vehicle that is directly in front of it is called a rear-end collision.
One of the most common accident in the United States is the
rear-end collision, and in a lot of cases, rear-end collisions are prompted by
drivers who are inattentive, unfavorable conditions of the road, and poor
following distance.
<span>An enough room in front of your car so you can stop when the
car in front of you stops suddenly is one basic driving rule. The person isn’t
driving safely if he / she is behind you and couldn’t stop.</span>
<span>The answer is: ultraviolet
The energy (E) of a photon is directly proportional to its frequency f, by Planck's
formula: E = hf, where h is Planck's constant (6.625 * 10**-34 joule-second).
The frequency is inversely proportional to the wavelength w by: f = c/w, where
c is the speed of light, 3.0 * 10**8 meters per second.
Combine these formulas and we see that the energy is inversely proportional to
the wavelength by: E = hc/w
If the energy is inversely proportional to the wavelength, a photon with twice the
energy has half the wavelength of our 442-nm. photon in this example.
So its wavelength is 221 nm. which is in the ultraviolet range.</span>
Answer: 6.9x 107 in standard form is 69,000,000
3. Sand has a low specific heat compared to air