Answer:
The force needed is the weight of the rock minus the buoyant force.
Explanation:
Answer:
B 14.5 m/s to the east
Explanation:
We can solve this problem by using the law of conservation of momentum.
In fact, if the system is isolated, the total momentum of the system must be conserved.
Here the total momentum before the stuntman reaches the skateboard is:
where
M = 72.0 kg is the mass of the stuntman
v = 15.0 m/s is his initial velocity (to the east)
The total momentum after the stuntmen reaches the skateboard is:
where
m = 2.50 kg is the mass of the skateboard
v' is the final velocity of the stuntman and the skateboard
Since momentum must be conserved, we have
And solvign for v',
And since the sign is the same as v, the direction is the same (to the east).
Recall that work is the amount of energy transferred to an object when it experiences a displacement and is acted upon by an external force. It is given a symbol of W and is measured in joules (J).
W=\vec{F}\cdot \Delta \vec{d}
We can use this formula to determine the work done by very specific forces, generating specific types of energy. We will examine three types of energy in this activity: gravitational potential, kinetic, and thermal. Before we start deriving equations for gravitational potential energy and kinetic energy, we should note that since work is the transfer and/or transformation of energy, we can also write its symbol as \Delta E.
There are usually no more than four trophic levels, because of the huge loss of energy at each trophic levels. Alomost 10 percent of the energy is lost at each level, as compared to the previous level, which occurs due to wastage of materials like bones and leftover tissues. So, till the fourth trophic level, very less energy is left to be continued to another level, and thus the process is like that.
C. 76 I just did the question earlier
