Answer:
D. The circulatory system transports oxygen that the respiratory system brings into the body.
Explanation:
the first two answers either refer to carbon dioxide as beneficial and necessary to the body(it sometimes is but not in this case)
the answer choice c refers to oxygen being transferred directly to the heart. This is also incorrect.
the only proper answer to this question is answer choice d.
Answer:
The force of friction is 2 N. The object isn't moving.
Explanation:
The frictional force on a object is given by it's normal force multiplied by the coefficient of static friction between the object and the surface. In this case since the surface is horizontal, the normal force is equal to the weight of the block with the oposite direction. So we have:
F_friction = 0.5*N = 0.5*(10) = 5 N
Since the friction force is oposite to force that's acting on the block and it's greater than that force, the object won't move and the real force will be the same as the applied force. So we have:
F_friction = 2 N
Answer:a)In a circuit, an electric field is created. This electric field forces electrons to move. ... A potential difference in a circuit merely means that work is done on electrons by an electric field as they pass through the circuit and their potential energy changes.b)When the two ends of a cell are connected to a bulb using metal wires, the bulb emits light. The bulb glows due to flow of electric current from the positive terminal to the negative terminal through the filament of the bulb. Such a circuit is called a closed circuit.
Explanation:
Answer:
iii) pressure is a vector quantity.
Answer: 1 cal is 4.186 J, 1 kcal = 4186 J A : 1014 m , B 200 m
Explanation: A) Work done by climber is change in potential energy.
W = ΔEp = mgh = 67.0 kg· 9.81 m/s²· h = 160 kcal · 4186 J / kcal.
Solve h = 160 kcal · 4186 J / kcal /67.0 kg· 9.81 m/s² = 1014 m
B Energy is only 20 % : Then h = 0.20 ·160 kcal · 4186 J / kcal /67.0 kg· 9.81 m/s² = 200 m.
Actually, muscles also produce heat from most of the energy provided by food.