Answer:
b. 0.6m/s, 0.7m/s, 0.61m/s, 0.62m/s
Explanation:
Precision of a measurement is the closeness of the experimental values to one another. Hence, experimental measurements are said to be precise if they are close to each other irrespective of how close they are to the accepted value. Precision can be determined by finding the range of each experimental value. The measurement with the LOWEST RANGE represents the MOST PRECISE.
Note: Range is the highest value - lowest value
Set A: 1.5 - 0.8 = 0.7
Set B: 0.7 - 0.6 = 0.1
Set C: 2.4 - 2.0 = 0.4
Set D: 3.1 - 2.9 = 0.2
Set B has the lowest range (0.1), hence, represent the most precise value.
Let say the two train cars are of masses 
and 
now if the speed of two cars are 
and 
then we can say that the momentum of two cars before they collide is given by
here two cars are moving in opposite direction so we can say that the net momentum is subtraction of two cars momentum.
Now since in these two car motion there is no external force on them while they collide
So the momentum of two cars are always conserved.
hence we can say that the final momentum of two cars will be same after collision as it is before collision
Answer:
If excess nitrogen is found in the crop fields, the drainage water can introduce it into ... have aquifers that can supply a lot of freshwater very near the land surface.
The refrigerator's coefficient of performance is 6.
The heat extracted from the cold reservoir Q cold (i.e., inside a refrigerator) divided by the work W required to remove the heat is known as the coefficient of performance, or COP, of a refrigerator (i.e., the work done by the compressor). The required inside temperature and the outside temperature have a significant impact on the COP.
As the inside temperature of the refrigerator decreases, its coefficient of performance decreases. The coefficient of performance (COP) of refrigeration is always more than 1.
The heat produced in the cold compartment, H = 780.0 J
Work done in ideal refrigerator, W = 130.0 J
Refrigerator's coefficient of performance = H/W
= 780/130
= 6
Therefore, the refrigerator's coefficient of performance is 6.
Energy conservation requires the exhaust heat to be = 780 + 130
= 910 J
Learn more about coefficient here:
brainly.com/question/18915846
#SPJ4
Explanation:
Given that,
The initial velocity of a skater is, u = 5 m/s
She slows to a velocity of 2 m/s over a distance of 20 m.
We can find the acceleration of skater. It is equal to the rate of change of velocity. So, it can be calculated using third equation of motion as follows :
a = acceleration
So, her acceleration is 
and she is deaccelerating. Also, her initial velocity is given i.e. 5 m/s.
