A Dodge Stealth is driving at 70 mph on a highway. It passes a BMW going the same direction. The BMW is moving 7 mph backward relative the Dodge. 63 mph is the velocity of the BMW
Answer: Option A
<u>Explanation:</u>
Given is the speed of the dodge stealth as 70 mph passing by the BMW moving with 7 mph relative to Dodge. Thereby, to calculate the velocity of BMW, relative velocity concept has to be employed.
As we know that the relative velocity tells us about relative velocity of mobile reference system as the difference or sum of the initial reference system.
Therefore,
velocity of the BMW = 
Velocity of the dodge = 
Velocity of the BMW with respect to dodge = 
As per the formula,


Answer:

Explanation:
Close to Earth's surface, the force of gravity that pulls an object towards the ground is
(2)
where
m is the mass of the object
g is the acceleration due to gravity, which is
close to Earth's surface
This is an approximation of the general formula of gravity valid only close to Earth's surface. The more general formula is
(1)
where
G is the gravitational constant
M is the Earth's mass
m is the object's mass
r is the distance of the object from Earth's center
At the Earth's surface,
r = R (Earth's radius), and by calling the following factor

we see that eq.(1) becomes eq.(2).
The (more) speed an object has, the (lower) the potential energy and the (higher) the kinetic energy. (I believe that is correct but it’s been a while since I’ve done this)
The motor bike can travel 225 kilometers on 5 liters of petrol
912.
outer ear:
pinna
ear canal
middle ear:
ossicles and ear drum
inner ear:
semcircular canals
cochlea
auditory nerve
13.
frequency = wavespeed ÷ wavelength
14.
if frequency increases you would experience a higher pitch in sound
15.
humans can hear 20Hz to 20kHz
16.
The Doppler effect is the change in frequency or wavelength of a wave for an observer who is moving relative to the wave source. Can be used for machines measuring speed via doppler effect.
17.
Doppler in hospitals can be used for ultrasound to provide images for diagnosis and monitoring.