Answer:
A. plot an H-R diagram for the stars in the cluster.
Explanation:
A star cluster can be defined as a constellation of stars, due to gravitational force, which has the same origin.
The astronomy student would have to plot an H-R diagram for the stars in the cluster and determine the age of the cluster by observing the turn-off point. The turn-off is majorly as a result of gradual depletion of the source of energy of the star. Thus, it projects off the constellation.
I would say b as well. I’m sorry if it’s wrong
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Answer:
1. The magnitude of the force from the spring on the object is zero on <em>Equilibrium.</em>
2. The magnitude of the force from the spring on the object is a maximum on <em>The top and bottom.</em>
3. The magnitude of the net force on the object is zero on <em>The Bottom.</em>
4. The magnitude of the force on the object is a maximum on <em>the Top.</em>
Explanation:
<em>1. Because the change in position delta X is zero.</em>
<em>2. Because of delta X.</em>
<em>3. Beacuse, the force of gravity and the force of the spring oppose each other to keep the block at rest, away from the equilibrium position.</em>
<em>4. Because, the force of the spring from compressiom and the force of gravity both act on the mass.</em>
Answer:
, where the minus indicates the direction is opposite to that of the throw.
Explanation:
a)
Since MKS stands for meter-kilogram-second and we know that:
We can write that:
These are conversion factors, equal to 1, so multiplying our results by them won't change their value, only their units.
So we have that:
b)
Newton's 2nd Law tells us that F=ma, and the definition of acceleration is 
, so we have:
Taking the throw direction as the positive one, for our values we have:
Answer:
the mass of water is 0.3 Kg
Explanation:
since the container is well-insulated, the heat released by the copper is absorbed by the water , therefore:
Q water + Q copper = Q surroundings =0 (insulated)
Q water = - Q copper
since Q = m * c * ( T eq - Ti ) , where m = mass, c = specific heat, T eq = equilibrium temperature and Ti = initial temperature
and denoting w as water and co as copper :
m w * c w * (T eq - Tiw) = - m co * c co * (T eq - Ti co) = m co * c co * (T co - Ti eq)
m w = m co * c co * (T co - Ti eq) / [ c w * (T eq - Tiw) ]
We take the specific heat of water as c= 1 cal/g °C = 4.186 J/g °C . Also the specific heat of copper can be found in tables → at 25°C c co = 0.385 J/g°C
if we assume that both specific heats do not change during the process (or the change is insignificant)
m w = m co * c co * (T eq - Ti co) / [ c w * (T eq - Tiw) ]
m w= 1.80 kg * 0.385 J/g°C ( 150°C - 70°C) /( 4.186 J/g°C ( 70°C- 27°C))
m w= 0.3 kg
