Answer:
an electromagnet is a metal which has the ability to turn into a magnet on passing electricity through it .
But once the electric flow is withdrawn the circuit breaks and it no more behaves like a magnet.
but this is not so in permanent magnets
Explanation:
thus electromagnet is used in magnetic cranes bcoz their magnetism can be controlled conveniently.
Answer:
58.5 m
Explanation:
First of all, we need to find the total time the ball takes to reach the water. This can be done by looking at the vertical motion only.
The initial vertical velocity of the ball is

where
u = 21.5 m/s is the initial speed
is the angle
Substituting,

The vertical position of the ball at time t is given by

where
h = 13.5 m is the initial heigth
is the acceleration of gravity (negative sign because it points downward)
The ball reaches the water when y = 0, so

Which gives two solutions: t = 3.27 s and t = -0.84 s. We discard the negative solution since it is meaningless.
The horizontal velocity of the ball is

And since the motion along the horizontal direction is a uniform motion, we can find the horizontal distance travelled by the ball as follows:

Answer:
How long will it take to travel a distance of 96 km? Givens. Solving For ... An object accelerates 3.0 m/s2 when a force of 6.0 Newtons is applied to it.
Explanation:
Answer:
The average speed during the trip is 6.16 
Explanation:
Speed is a physical quantity that expresses the variation in position of an object and as a function of time. In other words, speed expresses the relationship between the space traveled by an object, the time used for it and its direction.
The speed can be calculated by the expression:

Aaron rode his bike home for 1.6 hours at 6.5 km/h and another 15 minutes at 4 km/h. So, the distance in each of the stages can be calculated as, taking into account that 60 minutes= 1 hour:
- distance1=speed*time= 6.5
*1.6 hours= 10.4 km
- distance2= speed*time= 4
*15 minutes= 4
*0.25 hours= 1 km
So:
- total distance= 10.4 km + 1 km= 11.4 km
- total time= 1.6 hours + 0.25 hours= 1.85 hours
Then:


<u><em>The average speed during the trip is 6.16 </em></u>
<u><em></em></u>
Answer:
C) 4.0026 amu
Explanation:
Helium (He) is the 2nd element on the Periodic Table.
It's neutral atom has 2 protons and 2 electrons.
It is in the 1st period and the 18th row.
It is also a Noble gas.