Answer:
Explanation:
Mass =11.2kg
Constant velocity =3.3m/s
μk=0.25
Since the body is moving in constant velocity, then the acceleration is zero(0).
ΣF = Σ(ma)
The normal force acting on the body is upward and the weight is acting downward
Then ΣFy=0
Therefore, N=W
W=mg=11.2×9.8=109.76N
So, N=W=109.76N
Frictional force is given as
Fr=μkN
Fr=0.25×109.76
Fr=27.44N
Frictional force acting against the motion is 27.44N
Then the forward force moving the body forward
ΣF = Σ(ma)
Since a = 0
Then,
ΣF = 0
F-Fr=0
Then F=Fr
So the force moving the body forward is 27.44N
I am going to say velocity because you have the same amount of acceleration going in a certain direction.
The correct answers are:
B. plant growth;
C. animal actions;
The mechanical weathering is a type of weathering where physical force is included into the breaking up of the rocks. The plants and the animals are both causing this type of weathering with their actions. The plants can cause mechanical weathering with their roots, as they grow and surround a rock, they are able to create such a pressure that they can break the rock apart. Also, as their trunks are getting bigger, if there's rocks right next to them, the pressure from the growing of the trunk will crack the rocks. The animals are able to move the rocks, as well as pushing them, or even deliberately throwing them, so they manage to break up parts of them and cause mechanical weathering.
Answer:
Explanation:
Given:
- mass of car,
- distance of skidding after the application of brakes,
- coefficient of kinetic friction,
<u>So, the energy dissipated during the skidding of car:</u>
<em>Frictional force:</em>
where N = normal reaction by ground on the car
<em>Now from the work-energy equivalence:</em>
is the dissipated energy.
Answer: The drag force goes up by a factor of 4
Explanation:
The <u>Drag Force</u> equation is:
(1)
Where:
is the Drag Force
is the Drag coefficient, which depends on the material
is the density of the fluid where the bicycle is moving (<u>air in this case)
</u>
is the transversal area of the body or object
the bicycle's velocity
Now, if we assume , and do not change, we can rewrite (1) as:
(2)
Where 
groups all these coefficients.
So, if we have a new velocity 
, which is the double of the former velocity:
(3)
Equation (2) is written as:
(4)
Comparing (2) and (4) we can conclude<u> the Drag force is four times greater when the speed is doubled.</u>
