Answer:
0.66 s
Explanation:
∆x = v∆t → 2 × 115 = 350 ∆t → ∆t = 230/350 = 0.66 s
Answer:
C. 441 N
Explanation:
Gravitational force between two objects can by calculated by the formula
= G m₁m₂ / r² , m₁ and m₂ are masses at distance r
= ( 6.67 x 10⁻¹¹ x 45 x 5.98 x 10²⁴) / ( 6.38 x 10⁶ )²
= 44.09 x 10
= 440.9 N
= 441 N .
Gravity is the force that pulls you down.
(This is kind of a duh! question ... How do we know
which way is "down" ? We feel gravity, and we call
that the "down" direction.)
Magnetic force holds things to fridge doors.
Contact forces need to touch something in order to
exert their force.
Example: Gravity is NOT a contact force.
I don't know about "rubbing things away".
This might be a description of friction, but if so,
it's not a good one.
Buoyant force is what keeps floating things floating.
Air resistance slows things down when they move in air.
