You push on a block on frictionless ice with a force of 8 N, ...

[Cooldude101]

You push on a block on frictionless ice with a force of 8 N, causing it to accelerate at 2 m/s2 . The mass of the block is __________.
 Fill in the blank(s) with correct word

Question 2

The two photons produced in an electron-positron annihilation have equal but oppositely-directed momenta to match the zero momentum of the electron-positron pair. Which of the following conservation laws are obeyed in the pictured interaction?
 a. Conservation of energy.
  b. Conservation of momentum.
  c. Conservation of charge.
  d. Both a. and b. but not c.
  e. All of a., b. and c.

[gabrielle_lawrence]

Answer to Question 1

4 kg

Answer to Question 2

e

[Cooldude101]

Thanks for the timely response, appreciate it

[debra928]

Wow, this really help