A crate is given a push across a horizontal surface. The crate has a mass m, the push gives it an initial speed of 1.90 m/s, and the coefficient of kinetic friction between the crate and the surface is 0.120.

(a) Use energy considerations to find the distance (in m) the crate moves before it stops.

(b) Determine the stopping distance (in m) for the crate if its initial speed is doubled to 3.80 m/s.

Question 7 [2 marks] in the circuit below, the electromotive force generated by the battery is e = 6.0 v, and the resistances are r1 = r4 = 1.0 q, r2 = r3 =2.0 q. r. the power delivered by the battery to the circuit is closest to a. 6 w в. 12 w с. 15 w d. 18 w e. 20 w final exam autumn 2014 page 5 of 9 68037 physical modelling faculty of science [2 mark] question 8 with reference to question 7, the current through resistor r2 is closest to a. 1 a в. 2 а c. 3 a d. 4 a e. 6 a

Select all of the following that are equal to an impulse of 20 unitsa) force= 5, time= 5.5b) force= 25, time= 0.8c) force= 0.1, time= 200d) force= 10, time= 2(its b, c, and d)(also in order to find answer they have to add to get the unit)ex= 25x.8=20 or .1x200=20

If the chemical properties of a substance remain unchanged and appearance or shape of a substance changes it is called a ?