X-axis=time
y-axis=distance (position)
slope=y-axis / x-axis=distance / time=velocity.
answer: d) slope
Answer:
B= -40
The negative sign indicates the reverse direction to that of vector A.That is it is in the third quadrant.
Explanation:
Th resultant vector is obtained by adding the two vectors A and B
A + B= AB
25 + B= -15
25+ 15= -B
-B = 40
B= -40
Vector B has a magnitude of 40 and points in the opposite direction to that of vector A. The negative indicates the opposite direction.
When we reverse the vector B for adding we place a negative sign with the magnitude.
A vector is quantity defined by magnitude and direction. If the direction is left out it becomes a scalar.
Answer:
5.92×10⁷ J
Explanation:
We'll begin by converting 15 tons to Newton. This can be obtained as follow:
1 ton = 9806.65 N
Therefore,
15 ton = 15 ton × 9806.65 N / 1 ton
15 ton = 147099.75 N
Next, we shall convert one-quarter (¼) or 0.25 mile to metre. This can be obtained as follow:
100 mi = 160934 m
0.25 mi = 0.25 mi × 160934 / 100 mi
0.25 mi = 402.335 m
Finally, we shall determine the Workdone. This can be obtained as follow:
Force (F) = 147099.75 N
Distance (d) = 402.335 m
Workdone (Wd) =?
Wd = F × d
Wd = 147099.75 × 402.335
Wd = 5.92×10⁷ J
Thus, the Workdone is 5.92×10⁷ J
Answer:
The age of the universe would be 9.9 billion years
Explanation:
We can calculate an estimate for the age of the Universe from Hubble's Law. Let's suppose the distance between two galaxies is D and the apparent velocity with which they are separating from each other is v. At some point, the galaxies were touching, and we can consider that time the moment of the Big Bang.
Thus, the time it has taken for the galaxies to reach their current separations is:
and from Hubble's Law:
Therefore:
With the given value for the Hubble's constant we have:
and thus,
Lead-207 can change into Lead-208.
When Lead-207 is bombarded with neutrons, the atom acquires the neutron. Adding a neutron only changes the mass number of the atom. This does not involve change in the identity of the atom. So, Lead-207 can change into Lead-208 without change in its chemical properties.
