What is the acceleration of the blocks? what is the tension in the string?

Question

a 7.3N force pulls horizontally on a 1.7kg block that slides on a smooth horizontal surface. this block is connected by a horizontal string to a second block of mass m2= 0.81kg on the same surface.

Answer 1

F=ma but since the two blocks are connected here F=(m1+m2)a

so a=F/(m1+m2) a=7.3/(.81+1.7)

As for the tension, I believe that it is the same as the force pulling the two blocks but I'm not entirely sure.

Answer 2

First calculate the acceleration of both blocks:

F = ma

7.3 = (1.7+0.81)a

7.3 = 2.51a

a = 2.9 m/s^2

And from that, you can calculate the force required to accelerate the second block at that rate:

F = ma

T = 0.81 * 2.9

T = 2.4 N

If you just work out 0.81*2.9 it actually rounds to 2.3 N, but keeping the fully accurate values in the calculator leads to the rounded up value of 2.4 N.