Answer:
Plzzzzzzzzzzzzzzzz brainliest
Explanation:
In static friction, the frictional force resists force that is applied to an object, and the object remains at rest until the force of static friction is overcome. In kinetic friction, the frictional force resists the motion of an object. ... The frictional force itself is directed oppositely to the motion of the object.
As the length increases, resistance increases, as a result current decreases.
Explanation:
Assuming the wall is frictionless, there are four forces acting on the ladder.
Weight pulling down at the center of the ladder (mg).
Reaction force pushing to the left at the wall (Rw).
Reaction force pushing up at the foot of the ladder (Rf).
Friction force pushing to the right at the foot of the ladder (Ff).
(a) Calculate the reaction force at the wall.
Take the sum of the moments about the foot of the ladder.
∑τ = Iα
Rw (3.0 sin 60°) − mg (1.5 cos 60°) = 0
Rw (3.0 sin 60°) = mg (1.5 cos 60°)
Rw = mg / (2 tan 60°)
Rw = (10 kg) (9.8 m/s²) / (2√3)
Rw = 28 N
(b) State the friction at the foot of the ladder.
Take the sum of the forces in the x direction.
∑F = ma
Ff − Rw = 0
Ff = Rw
Ff = 28 N
(c) State the reaction at the foot of the ladder.
Take the sum of the forces in the y direction.
∑F = ma
Rf − mg = 0
Rf = mg
Rf = 98 N
Answer:
The balloon hit the ground with velocity -15.34 m/s
Explanation:
<em>Lets explain how to solve the problem</em>
You found that the best height to pitch a water balloon in order for it to
burst when it hits the ground is 12 meters.
We consider that the 12 meters is the maximum height, so the velocity
at this height is zero.
To find the velocity when the balloon hits the ground lets use the rule
<em>v² = u² + 2gh</em>, where v is the final velocity, u is the initial velocity, g is
the acceleration of gravity and h is the height.
u = 0 , h = 12 m , g = 9.8 m/s²
<em>Substitute these values in the equation above</em>
v² = 0 + 2(9.8)(12)
v² = 235.2
<em>Take square root for both sides</em>
v = ± 
The velocity is downward, then it's a negative value
Then v = -15.34 m/s
<em>The balloon hit the ground with velocity -15.34 m/s</em>
The answer would be a.
a chemical change is a change to the chemical makeup of a substance so if the bonds are unchanged it would be a characteristic of a physical change
