Answer:
T= 224.01 N
Explanation:
in imminent motion we have to :
- The frictional force reaches its maximum value
- The system is in balance of forces
Data
W= 500 N : weight of the log
μs = 0.5
μk = 0.35
α = 30°above the ground : angle of the cable attached to the log
Newton's first law to the log:
∑F =0 Formula (1)
∑F : algebraic sum of the forces in Newton (N)
Forces acting on the log
T: cable tension for impending movement
N: normal force
W : weight
f: frictional force , f= μsN
We apply the formula (1)
∑Fx=0
Tx-f = 0
Tcosα-μsN=0
Tcos30°-0.5N=0 Equation (1)
∑Fy=0
N+Ty-W=0
N+Tsin30°-500=0
N= 500-Tsin30° Equation (2)
We replace the value of N of the Equation (2) in the equation (1)
Tcos30°-0.5(500-Tsin30°) = 0
Tcos30°+0.5Tsin30° = 0.5*500
T( cos30°+0.5*sin30°) = 250
(1.116) T = 250
T= 250/1.116
T= 224.01 N
The speed of the ball is B. 5 meters per second
Explanation:
For an object in uniform motion (= at constant velocity), the speed can be calculated using the equation
where
v is the speed
d is the distance covered
t is the time taken
For the ball in this problem:
d = 50 m is the distance covered
t = 10 s is the time taken
Substituting, we find the speed:
Learn more about speed:
brainly.com/question/8893949
#LearnwithBrainly
<h3>
Answer: A. Kelvin</h3>
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Explanation:
At 0 Kelvin, we're at the coldest temperature possible which is referred to as absolute zero. We cannot get any colder than this. At this temperature, the molecules aren't moving or vibrating to provide heat energy. The higher the temperature, the more the molecules are moving or vibrating.
The 0 degree mark on the Celsius scale is well above absolute zero. So that allows for negative Celsius temperatures to be possible. The same can be said about Fahrenheit as well. We cannot have negative Kelvin temperatures.
There are 3 types of faults, strike-slip fault, normal fault and reverse fault. So choices a and d will no longer be considered. Now the difference between a normal fault and a reverse fault is in a normal fault the hanging wall moves downwards and in a reverse fault the hanging wall moves upwards.
So considering the two faults and their characteristics, the answer would be b. reverse fault.
Answer:
A paper being burned is a chemical change.
