Answer:
The force required to move the quarterback with linebacker is <u>1215 N</u>
Explanation:
Using Newton's second law, it is established that F = Ma
Where F is net force acting on the system, a is the acceleration and M is mass of the two object 
Now consider both 
as a system, so net force acting on the system is 
Substitute the given values in the above formula,
Force = 1215 N
<u>1215 N </u>is the force required to move the quarterback with linebacker.
When the magnet is placed on the glass, it is attracted to the iron filings. The pattern of the iron filings shows that the lines of force that make up the magnetic field of the magnet. Also, The lines of force of north and south poles attract each other whereas those of two north poles fend off each other.
Explanation:
Red, green, and blue are therefore called additive primaries of light. ... When you block two lights, you see a shadow of the third color—for example, block the red and green lights and you get a blue shadow. If you block only one of the lights, you get a shadow whose color is a mixture of the other two.
First, your definition of a shadow is incorrect. A shadow is an area that receives less light than its surroundings because a specific source of light is blocked by whatever is "casting" the shadow. Your example of being outside reveals this. The sky and everything around you in the environment (unless you are surrounded by pitch black buildings) is sending more than enough light into your shadow, to reveal the pen to your eyes. The sky itself diffuses the sunlight everywhere, and the clouds reflect plenty of light when they are not directly in front of the Sun.
If you are indoors and have two light bulbs, you can throw two shadows at the same time, possibly of different darknesses, depending on the brightness of the light bulbs.
It can take a lot of work to get a room pitch black. One little hole or crack in some heavy window curtains can be enough to illuminate the room. There are very few perfectly dark shadows.
#3). Your drawing in the lower right corner is correct. You're headed down the right road, but ran out of gas and just stopped.
Radius of the circle = 1.5 km
Circumference of the whole circle = (2·π·radius) = 9.42 km
Distance = 3/4 of the way around it = 7.07 km .
Displacement = the straight line from the West point to the North point. The straight-line length is 2.12 km; the straight-line direction from start to finish is Northeast (45°). I'll let you figure out why these numbers.
#4). What if you walk 1 mile East and then 1 mile West ? You got a good workout, and you're back home where you started ! Your distance is 2 miles, and your displacement is zero.
The whale had a good workout too. She swam (6.9 + 1.8 + 3.7) = 12.4 km. She's sweating and tired. Her total distance during that workout is 12.4 km.
Her displacement is the line from start-point to end-point. How she got there doesn't matter, so swimming 1 km East and then swimming 1 km West cancel out, and have no effect on the displacement.
(6.9E + 1.8W + 3.7E) = (10.6 E) + (1.8 W) . . . That adds up to 8.8 East ! That's where she ends up. That's her displacement ... 8.8 km East of where she started. Since we're only talking about displacement, we don't care HOW she got there. She might have been swimming big 20-km circles all day. We don't know. All we know is that she ended up 8.8 km East of where she started.
