Answer:
Average power output of athlete = 11025 Watts
Explanation:
Work done is defined as the product of force applied and the displacement perpendicular to the force.
Work = 
Power is defined as work done per unit time.
Power = 
Here the person lifts 900 kg.
Height = 2.5 m
Time interval = 2 seconds
Force = 
= 
= 8820 N
Work done =
= 
= 22050 J
Power = 
= 11025 Watt
Answer:
Explanation:
Given:
- mass of the object,
forces by two mutually perpendicular ropes of the attached to the object:
<u>Now we find the resultant force effect due to the two given forces:</u>
<u>Now the acceleration will be due to this resultant force:</u>
Answer:
<em>The coefficient of static friction between the crate and the floor is 0.41</em>
Explanation:
<u>Friction Force</u>
When an object is moving and encounters friction in the air or rough surfaces, it loses acceleration and velocity because the friction force opposes motion.
The friction force when an object is moving on a horizontal surface is calculated by:
[1]
Where 
is the coefficient of static or kinetics friction and N is the normal force.
If no forces other then the weight and the normal are acting upon the y-direction, then the weight and the normal are equal in magnitude:
N = W = m.g
The crate of m=20 Kg has a weight of:
W = 20*9.8
W = 196 N
The normal force is also N=196 N
We can find the coefficient of static friction by solving [1] for :
The friction force is equal to the minimum force required to start moving the object on the floor, thus Fr=80 N and:
The coefficient of static friction between the crate and the floor is 0.41
Answer:
<h2>33.53m/s</h2>
Explanation:
Given the maximum speed limit on interstate 10 as 75 miles per hour, to get the speed in meter per seconds, we need to convert the given speed to meter per seconds.
Using the conversion 1 mile = 1609.34m and 1 hour = 3600 seconds
75 miles perhour = 75miles/1 hour
75miles/1 hour (in m/s) = 75miles*1609.34m* 1 hour/1mile * 1 hour * 3600s *
= 75 *1609.34m* 1 /1 * 1 * 3600s
= 120,700.5m/3600s
= 33.53m/s
<em>Hence the maximum speed limit on interstate 10 in metre per seconds is 33.53m/s</em>
Answer:
1. True WA > WB > WC
Explanation:
In this exercise they give work for several different configurations and ask that we show the relationship between them, the best way to do this is to calculate each work separately.
A) Work is the product of force by distance and the cosine of the angle between them
WA = W h cos 0
WA = mg h
B) On a ramp without rubbing
Sin30 = h / L
L = h / sin 30
WB = F d cos θ
WB = F L cos 30
WB = mf (h / sin30) cos 30
WB = mg h ctan 30
C) Ramp with rubbing
W sin 30 - fr = ma
N- Wcos30 = 0
W sin 30 - μ W cos 30 = ma
F = W (sin30 - μ cos30)
WC = mg (sin30 - μ cos30) h / sin30
Wc = mg (1 - μ ctan30) h
When we review the affirmation it is the work where there is rubbing is the smallest and the work where it comes in free fall at the maximum
Let's review the claims
1. True The work of gravity is the greatest and the work where there is friction is the least
2 False. The job where there is friction is the least
3 False work with rubbing is the least
4 False work with rubbing is the least
