Senior 1 Physics Compulsory 1 2 The answers to the experimental questions have a detailed process pr

Answer: 1:2;1/2v0t0；4:1

Analysis: According to the momentum theorem, ft = mv, in the process of relative motion of a and b, their combined external forces are equal, and the ratio of the change in velocity is 2:1, so the ratio of mass is 1:

2；The minimum length of b is equal to the difference between the displacements of a and b in the process of relative motion, and the difference between the displacements of a and b is equal to the area of the triangle in the figure s=1 2v0t0; From the kinetic energy theorem, it can be seen that the work done by the resultant external force is equal to the amount of change in the kinetic energy of the object, and in this problem, the combined external force for a and b is equal to the frictional force, so the ratio of the work done by the frictional force is equal to the ratio of the change in the kinetic energy of the object, which is 4:1.

1.Analysis: After the water is sprayed, it does a flat throwing motion.

Displacement decomposition: h= x=vot

t= vo= can be solved

Ejection volume per second v=vots = cubic meters.

2.After the parts fly out, they do a flat throwing motion.

Displacement decomposition: h= x=vot

t= vo= can be solved

So overspeeding.

4.Analysis: The horizontal motion of the object and the vertical motion of the object do not interfere with each other. The vertical direction is from the big silver to the falling body, and the water fights in the flat direction to accelerate the movement.

1) T time, vy=gt vx=at. where the horizontal direction is f=ma, a=f m.

So vy=gt,vx=ft m

2)x= ——

y=ratio:y=fx gm, the trajectory is a straight line.

/（234/60）=

3. The T108 train stopped at Liaocheng Station at 9:28 and 9:36, so the instantaneous speed at 9:30 was 0

It's high school, and it's a junior high school problem!

The key is to test your ability to know, understand, apply and convert time units of train timetables!

The known quantities required by this problem are all in the timetable, and the corresponding quantities are calculated by substituting the corresponding quantities into v=s t!

Specific as recommended, but there must be details of formulas and units!

If you don't have a book, you don't know anything else, so let's do this one.

Let the mass of calcium carbonate required for the reaction be x, and the mass of calcium chloride shall be y

Find the carbon dioxide quality first:

The amount of substances of CO2 gas = =

The relative molecular mass of CO2 = 44

So the mass of CO2 gas = 44* = 22g

Chemical equation: CaCO3+2HC---CaCl2+CO2+H2O

x y 22

100/x=111/y=44/22

x=50g,y=

90% of calcium carbonate requirements are 50 90% =

The amount of calcium chloride substance is n=m m=

Do you need an answer in the lab manual?

According to the law of flat throwing motion,,, there is a formula to solve v0=, so the car is speeding.

Analysis: When the block is thrown horizontally, the centripetal force is provided by gravity at the highest point on the belt, the critical velocity is calculated according to Newton's second law, and the minimum number of revolutions per second of the A wheel is found according to the relationship between the linear velocity and the rotational speed

It should be the choice of C The tangent point of the object is the centripetal force provided by the gravity of the object at the tangent point that is about to leave the pulley, that is:

mg=mv2 r can be solved for the critical velocity for the answer c

The centripetal force of the selected C object is mg, and the radius of circular motion is r

mg=rmv2

v = root number under gr