They need more oxygen to function, so gas exchange needs to increase
The figure shown below illustrates a lever being used to lift a weight W.
The applied force is F.
In order to lift the weight, the minimum applied force is
F*b = W*a
F = (a/b)W
When the ratio a/b < 1, then the applied force is less than the weight.
The principle behind the use of a lever is to keep the ratio a/b small in order to decrease the effort force.
Answer: A
A lever is used to decrease effort force.
Answer:
Less than 18000N
Explanation:
Given

This question will be answered using Newton's third law.
Understanding this law, it implies that reaction force is equal and opposite to the force exerted.
This implies that;
If the force exerted on the ball is 18000N
the force exerted is -18000N
So, the option that answers the question is less than 18000N because -18000N < 18000N
Answer:
11.8 m/s
Explanation:
At the top of the hill, there are two forces on the car: weight force pulling down (towards the center of the circle), and normal force pushing up (away from the center of the circle).
Sum of forces in the centripetal direction:
∑F = ma
mg − N = m v²/r
At the maximum speed, the normal force is 0.
mg = m v²/r
g = v²/r
v = √(gr)
v = √(9.8 m/s² × 14.2 m)
v = 11.8 m/s
Answer: Trajectory=51m
Displacement=41m
Explanation:
Let's begin by stating clear that <u>movement is the change of position of a body at a certain time.</u> So, during this movement, the body will have a trajectory and a displacement, being both different:
The trajectory is the path followed by the body (is a scalar magnitude).
The displacement is the distance in a straight line between the initial and final position (is a vector magnitude).
According to this, in the description of the object placed at x= -7m on a number line and moving some 12m to the left and then to the right, stopping at x=34m; we are talking about the path followed by the object, hence its <u>trajectory</u>. So, 51 m is its trajectory.
But, if we talk about displacement, we have to draw a straight line between the initial position of the object (x=-7m) to its final position (x=+34m).
Now, being this an unidimensional problem, the displacement vector for this object is 41m.