Question

sara is playing hockey with her friends identify the force answer​

Answer 1

Answer:

hope it helps you

Explanation:

What can you do with 100 battery-powered toy cars? Why does a rocket go up when its thrusters are pointing down? Why should you carry your grocery bags at your elbows instead of in your hands? The answers to these questions and more lie ahead.

You’ll likely not have to think long to come up with an everyday situation you could easily describe in terms of force and motion. Some aspects are probably quite intuitive, but others might be less so. Consider this: You’re riding your bike and you’re stopped at an intersection. The light turns green, and you get yourself back up to cruising speed. You could easily — and accurately — replace the last clause of the previous sentence with ‘and you accelerate away from the balk line.’ You know that if you’re changing your velocity, you’re accelerating. But if you’re accelerating, there must be a net force on the you + your bike system. What sort of force is driving your acceleration? How would we describe the situation if you were turning at the intersection instead of going straight through? Let’s develop our understanding a bit more.

Theory

You’re likely familiar with the idea that acceleration is speeding up, but physicists have a broader definition that incorporates speeding up, slowing down, and changing direction. Acceleration is a vector quantity — to completely describe an object’s acceleration, you must know both the magnitude and the direction of the acceleration. Specifically, we define acceleration as the change in an object’s velocity per unit time. Velocity, in turn, is specifically the amount of and direction of change in position per unit time. (A note here: Velocity is not the same as speed! Velocity is a vector quantity too, and speed is just the magnitude of the velocity vector. To define a velocity, we must include the direction of travel.)

Forces are the reason things speed up, slow down, or change direction — i.e., the reason that things accelerate. Broadly speaking, a force is a push or a pull (so, as you might expect, force is another vector quantity). If there’s no net force on a moving object, its velocity won’t change — this is Newton’s first law (of three). By the same token, if there is a net force on an object, its velocity will change — it will accelerate. This is Newton’s second law [specifically, Newton’s second law states that a = Fnet ÷ m: an object’s acceleration (in m/s2 — i.e., meters per second per second) is the quotient of the net force acting on it (in Newtons, N) and its mass (in kilograms, kg); a and Fnet are both vector quantities, but m is not, so the direction of Fnet defines the direction of a]. You’ve probably heard Newton’s third law described thus: “Every action has an equal and opposite reaction.” There’s some truth in this, but we can make the physical facts of the matter much more clear.

Let’s do this by returning to the question we asked above: What force causes you + your bike to accelerate forward when you pull away from an intersection? You might think you’re pushing yourself forward, but this is not physically possible. We say that the entity which exerts a force is the ‘agent’ and that which the force is exerted upon is the ‘object’; an object cannot be its own agent — you can’t exert a net force on yourself. However, the object can and absolutely does exert a force on the agent that is equal in magnitude and opposite in direction to the force the agent applies to the object. This is really what Newton’s third law tells us: A force is never alone. It always has a mirror-image twin that’s acting on the agent of the first force. (This is why you can’t exert a net force on yourself — the action and reaction force vectors cancel one another.) Think about the point where your bike tires meet the road. The tires are moving opposite the direction of your overall velocity — the tires are pushing backward on the road. We know, then, that the road must be pushing forward on your tires. If this forward force from the road is larger than the backward force from the air you have to push out of the way as you move, there is a net forward force on you, so you accelerate forward. (Note that Newton’s third law makes no comment on the relative effects of each force — the road’s mass is much, much larger than yours, so even though you push backward on it with the same magnitude force it pushes forward on you with, the road’s acceleration is negligible.)

Before we move on to applications and experiments, let’s take a few moments to talk about different types of forces and how we analyze them — this will help us more clearly and fully describe what we see in the videos to follow. All of these forces fit the general definition of a force we used above.

Answer 2

Answer:

muscular force Mark me brainliest

Explanation:

As the hockey player pushes off with his rear leg, a perpendicular force F is exerted on the skate by the ice. The component of the force F that points forward (in the direction of motion) is what pushes the player forward. At the same time, his other skate is either raised or gliding on the ice.