Answer:
Explanation:
In order to measure the coefficient of friction , we apply external force to move the body . When external force comes in motion , we adjust the external force so that it moves with zero acceleration or uniform velocity . In this case external force becomes equal to kinetic frictional force and then net force becomes zero because
net force = mass x acceleration = m x 0 = 0
Now frictional force = μ mg where μ is coefficient of kinetic friction
so F = μ mg where F is external force applied
μ = F / mg
Hence , to make external force equal to frictional force , it is necessary to make acceleration of body zero .
Answer:
speed of current is 5 mile/hr
Explanation:
GIVEN DATA:
speed of motorboat = 15 miles/hr relative with water
let c is speed of current
15-c is speed of boat at upstream
15+c is speed of boat at downstream
we know that
travel time=distance/speed

150+10c+150-10c=1.5(15-c)(15+c)
300=1.5(225-c^2)
300=337.5-1.5c^2
200=225-c^2
c^2=25
c = 5
so speed of current is 5 mile/hr
<span>Electromagnetic
radiation are represented in waves. Each type of wave has a certain shape and
length. The distance between two peaks in a wave is called the wavelength. It
is indirectly related to the frequency which is the number of wave that pass
per unit of time. Wavelength is equal to the speed of light divided by the
frequency. We calculate as follows:
Wavelength = </span>300,000,000 m/sec / <span>650,000,000,000,000 per second
Wavelength = 4.62x10^-4 m</span>
Reducing the amount of loops will cause a loss of strength, as the loops make the magnet stronger.