Blocks A and B of masses 19 kg and 15 kg, respectively, are connected by a rope that passes over a light frictionless pulley as shown. Horizontal surface is rough. The static and kinetic friction coefficients are 0.40 and 0.20, respectively. External forces P and Q act on block B as shown. In the figure, the force P is equal to 60 N. What is the approximate maximum value of Q force at which the system remains at rest?

powerful computers now, not then

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.

part 1: which substance has a higher solubility?

a

smallest amount left undissolved atall temps in table shown most has dissolved high sol'by

the best answer for these questions would be:

1.            c. is smaller

2.            d) concrete operational

3.            b) interaction with the environment – the children interact with their environment can them learn more.

4.            a) parents who reason openly with children can limit a child’s cognitive ability.