An electromagnet is made from a coil of wire which acts as a magnet when an electric current passes through it. Often an electromagnet is wrapped around a core of ferromagnetic material like steel, which enhances the magnetic field produced by the coil.
The answer is so that everyone is measuring the same distance and counting that distance as the same everywhere. one example from real life why it is important to use standard units is the loss of the NASA mars orbiter. some people decided that the units were to be in metric and others thought that the units were in imperial (english) system. so the orbiter was lost.
let's eliminate some choices
A. to allow for consistientcy with measurement data:
not really, just make sure the instruments are accurate.
B. to use tools marked in customary units: this could be true because a custom is something that is accepted in a wide area and if it is standard, then it is customary so b is the answer
C. so they can keep measurement data secret: nope
D. to record with easier abbreviations: not really
the answer is B
Answer:
Explanation:
a) Total distance traveled by the whale = 6.9 km + 1.8 km + 3.7 km = 12.4 km
b) the magnitude and the direction of the displacement of the whale = 6.9 km due east - 1.8 km due west = 5.1 due east
it final displacement = 5.1 km due east + 3.7 k due east = 8.8 km due east
c) average speed in km / hr = total distance traveled / total time = 12.4 km / 0.5 hr ( 30 min/ 60 min × 1 hr) = 24.8 km / hr
d) average velocity in km / h = total displacement / total time = 8.8 km / 0.5 h = 17.6 km/h
Answer:
u=78.4m/s
Explanation:
A ball is thrown vertically upward, which is the positive direction.A little later it returns to its point of release.The ball is in the air for a total time of 8.0 s.What is its initial velocity? Neglect air resistance
from newtons equation of motion
s=ut
v=u+at
v=0 because at maximum height reached by the ball the ball stops moving
0=u-9.8*8
u=78.4m/s
u=initial velocity
v=final velocity
a=acceleration due to gravity, 9.81m/s^2
t=time it takes in air
s= distance to get to the maximum before returning
