Answer:
Sleeping, since your brain is working, but your physical body is not moving at all or moving rarely, therefore there is no work done in the activity of sleeping.
Explanation:
Answer:
I think -7 N. Netforce is 3N-10N= -7N
Explanation:
Answer:
B, the car travels around a circular track at 30 m.
Explanation:
Answer:
Explanation:
Since the universal SI unit for velocity is meters/second, let's convert ft/s to m/s:
We can use the following kinematics equation to solve this question:
What we know:
- The initial velocity,
, is 
- (physics concept) The final velocity must be equal in magnitude but opposite in direction to the initial velocity (
) - Acceleration,
, is acceleration due to gravity at about 
Solving for 
:
You can reason it out like this:
-- The car starts from rest, and goes 8 m/s faster every second.
-- After 30 seconds, it's going (30 x 8) = 240 m/s.
-- Its average speed during that 30 sec is (1/2) (0 + 240) = 120 m/s
-- Distance covered in 30 sec at an average speed of 120 m/s
= 3,600 meters .
___________________________________
The formula that has all of this in it is the formula for
distance covered when accelerating from rest:
Distance = (1/2) · (acceleration) · (time)²
= (1/2) · (8 m/s²) · (30 sec)²
= (4 m/s²) · (900 sec²)
= 3600 meters.
_________________________________
When you translate these numbers into units for which
we have an intuitive feeling, you find that this problem is
quite bogus, but entertaining nonetheless.
When the light turns green, Andy mashes the pedal to the metal
and covers almost 2.25 miles in 30 seconds.
How does he do that ?
By accelerating at 8 m/s². That's about 0.82 G !
He does zero to 60 mph in 3.4 seconds, and at the end
of the 30 seconds, he's moving at 534 mph !
He doesn't need to worry about getting a speeding ticket.
Police cars and helicopters can't go that fast, and his local
police department doesn't have a jet fighter plane to chase
cars with.
