Rate of change of momentum = impact force
(m*v-m*u)/t = F
4000*20/t = 80000 (note: v is zero as it stopped)
<span>soo, t = 1 sec</span>
Answer:
Explanation:
A correlation of +0.95 between two variables signifies a strong positive relationship between the two measured variables (the dependent and independent). The value is usylay called the correlation Coefficient (r) as it measures the level or degree of relationship or correlation between two measured linear variables. The value ranges between - 1 and +1 with + signifying a positive relationship (increase or decrease in one variable leads to corresponding increase or decrease in the other) while a negative correlation means (a decrease in A leads to increase in B and vice versa). A correlation Coefficient of 0 means no relationship and the strength of the relationship increases as the value approaches - 1 or +1.
<span>The first three steps in scientific inquiry are related in that they are all equivalent to being on a fact finding mission. The three steps are to find or develop the question that must be answered, to study all related academic literature on the subject, and then to make a guess as to what the answer is.
I hoped I helped!</span>
Astronomers believe the sun like other stars was formed within a nebula
Answer:
The correct answer is a) The kinetic energy of the ice increases by equal amounts for equal distances.
Explanation:
The law of conservation states that the energy cannot be created nor be destroyed but can be converted from one form to another.Before the ice even starts falling we already know that it possesses energy in the form of potential energy given by P=mgh where m is the mass of the ice , g is the acceleration due to gravity and h is the height of the ice above the ground whatever that may be, since a number is not given here.As the ice falls the energy is converted from potential energy to kinetic energy. We notice one thing about the equation for the potential energy P , which is that it is not only directly proportional to h but also is linear in h as well(which is the main reason why a) is correct) which means that if the ice drops by 1 meter the potential energy it will have lost would be ΔPE=mgΔh=-mg, where Δh is the change in its height which is 1 meter here.And according to the principle of conservation of energy this energy must be converted to kinetic energy so the ΔKE=-ΔPE=mg, and this process repeats and for each meter it falls, it picks up the same amount of kinetic energy equaling mg(which is the same as the loss in PE per each meter of fall). So a 2 meter decrease in height will result in an increase in KE of 2mg, a 3 meter decrease in height will result in an increase in KE of 3mg. gain in kinetic energy only depends on the drop in height, which is true irrespective of where the ice might happen to be in its journey close to the top or the bottom. So the drop in height of lets say x at any point in the journey will result in the same increase in KE = ΔKE = mgx. Which proves part a) to be correct.