Answer:
Sinkhole fatalities are rare, but they do occur sometimes. Also fatalities are more likely where sinkholes are common. For example, sinkholes are more common in Florida than in California, so you would more likely die from a sinkhole in Florida than you would in California.
Hope this helps!
Infrared radiation <span>is sensed by human skin as warmth.</span>
Answer:
the power dissipated P = cd A v³
The speed increase percentage is 3.79
Explanation:
The power is defined as the change of work by the unit of time, as the work is the product of the force by the distance, we can rewrite the power, where the bold ones indicate vectors and the point is the scalar product.
P = F .v
In the current case, the force always opposes the speed, so the product is negative, which indicates a dissipative power.
Let's write the dissipation force and calculate
Fdrag = Cd A v²
P = Cd A v² v
P = cd A v³
this is the power dissipated
Second part
We write the expressions for the dissipated power for Po and P1
Po = Cd A vo³
P1 = 110 Po
P1 = Cd A v1³
We replace
110 Po = Cd A v13
110 (Cd A Vo³) = Cd A v1³
simplify
110 Vo3 = v13
v1 = ∛110 vo
We look for the one that increases the speed
(v1-vo) / vo = (∛110 vo-vo) / vo
(v1-vo) / vo = ∛110 -1
(v1-vo) / vo = 3.79
The speed increase percentage is 3.79
Answer:
<em>Magnitude of frictional force = 30 N</em>
Explanation:
According to the second Newton's law, the net force exerted by an external agent on an object of mass m is:
Fn=m.a
The net force is the vector addition of each individual force. If the sum of all the forces acting on an object is zero, then the acceleration is zero. That means the object moves at a constant speed or is at rest.
When an object is pushed across a horizontal rough surface, there are two forces acting in the direction of the motion: The applied force and the frictional force.
If the applied force is greater than the frictional force, then the object moves at a constant positive acceleration. If the frictional force is greater than the applied force, then the object won't move at all (if it was at rest) or will start a deaccelerated motion (braking).
Finally, if both forces are equal, the object will move at a constant speed or remains at rest. Since the box is moving at a constant speed, we can conclude the frictional force equals the applied force:
Magnitude of frictional force = 30 N
Answer:
D. 6 m/s²
Explanation:
Given parameters:
Initial velocity = 36m/s
Final velocity = 0m/s
Time taken = 6s
Unknown:
Acceleration of the car = ?
Solution:
Acceleration is the rate of change of velocity with time;
Mathematically;
Acceleration = 
v is the final velocity
u is the initial velocity
t is the time
Acceleration = 
= -6m/s
The acceleration of the car must have been 6m/s²
