False. An Electromagnetic induction is the production of an electromotive force across an electrical conductor in a changing magnetic field.
Explanation:
Solution,
- Mass(m)= 60 kg
- Force (F)= 20 N
- Acceleration (a)= ?
We know that,
- F=ma
- a=F/m
- a=20/60
- a=0.333 m/s²
So, her acceleration is 0.333 m/s².
b. 460.8 m/s
Explanation:
The relationship between the speed of the wave along the string, the length of the string and the frequency of the note is

where v is the speed of the wave, L is the length of the string and f is the frequency. Re-arranging the equation and substituting the data of the problem (L=0.90 m and f=256 Hz), we can find v:

c. 18,000 m
Explanation:
The relationship between speed of the wave, distance travelled and time taken is

where
v = 6,000 m/s is the speed of the wave
d = ? is the distance travelled
t = 3 s is the time taken
Re-arranging the formula and substituting the numbers into it, we find:

Answer:
A solenoid is a device comprised of a coil of wire, the housing and a moveable plunger (armature). When an electrical current is introduced, a magnetic field forms around the coil which draws the plunger in. More simply, a solenoid converts electrical energy into mechanical work.
Explanation:
The coil is made of many turns of tightly wound copper wire. When an electrical current flows through this wire, a strong magnetic field/flux is created.
The housing, usually made of iron or steel, surrounds the coil concentrating the magnetic field generated by the coil.
The plunger is attracted to the stop through the concentration of the magnetic field providing the mechanical force to do work.
For this case, the first thing you should know is that the length of a football field is around 100 meters.
We must then look for a measure close to this value.
We have the following unit conversion:
1 meter = 10 decimeters
Applying the conversion we have:

Therefore, the measure closest to a soccer field is:
1000 dm
Answer:
The length of a football field is closest to:
(2) 1000 dm