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How to use the formula of uniform variable speed linear motion in senior high school physics compulsory 1 Is under what circumstances this formula is used
It is suitable for uniform speed linear motion. That is, the resultant force on the object is a constant force (the size remains the same, and the direction remains the same)
To solve the problem of uniform variable speed linear motion, we must first analyze the physical process, the force on the object, and the size and direction of the speed, acceleration and displacement of the object, which are known and which are unknown. If there are two or more processes, we must find the link connecting the adjacent processes - the relevant physical quantity, generally the final speed of the previous process, This is the initial velocity of the latter process
In addition, pay attention to the direction of the vector (the + - sign when substituting into the formula). Generally, the direction of the initial velocity is specified as the positive direction, so the signs of velocity, acceleration and displacement are determined
In addition, it is more convenient to use the average velocity to calculate the displacement or time as much as possible
For high school physics compulsory 1 Chapter 2 uniform speed linear motion formula, inference and use! The inference is the motion characteristic with an initial speed of 0, a few to several! Be sure to be complete and indicate the use! There are many, answer well,
Are you talking about when the initial velocity is zero,
In the same time interval, the ratio of speed V1: V2: V3:...: VN = 1:2:3:4............:
The derivation formula is VT = V + at. You take t = 1, t = 2... One by one. Remember, all start from scratch, that is, V should be zero, bring in T, and it's very troublesome to calculate in segments
I don't know if you're talking about this. For example, there are too many words to type
High school physics can only be used to find the formula of uniform variable speed linear motion
Motion of flat projectile
Uniform circular motion
Uniform speed linear motion formula
1、 Motion of particle (1) ---- linear motion 1) uniform speed linear motion 1. Average speed vping = s / T (definition formula) 2. Useful inference vt2-vo2 = 2as3. Intermediate time speed VT / 2 = vpping = (VT + VO) / 2 4. Final speed VT = VO + at5. Intermediate position speed vs / 22 = (VO2 + vt2) / 2 6. Displacement s
High school physics free fall The water emits vertically downward from the faucet with a flow rate of q = 1.1 * 10-2m2 / s. if the planting area at the faucet outlet is S0 = 11cm2, what is the planting area s of the water at h = 1.05M directly below the faucet outlet? How? thank you
Outlet speed V0 = q / S0 = 10m / S
Velocity at lower h VT = root sign (V0 square + 2GH) = 11m / S
If the flow here is also Q, then
s=Q/vt=10cm2
If you have any questions, just hi me
The elevator with height h descends at a constant speed V, and an object falls freely on the top of the elevator. The time when it touches the bottom of the elevator is compared with that when the elevator is stationary () A. Longer B. Shorter C. Same D. It is related to the speed of the elevator, so it cannot be determined
Taking the elevator as the reference system, compared with the elevator, the object moves freely in both cases; Then the falling displacement is equal and the time must be equal;
Therefore: C
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