Question Number 25252 by NECx last updated on 07/Dec/17
$${The}\:{mass}\:{of}\:{earth}\:{is}\:\mathrm{5}.\mathrm{98}×\mathrm{10}^{\mathrm{24}} {kg}. \\ $$$${If}\:{the}\:{earth}'{s}\:{gravitational}\:{force} \\ $$$${causes}\:{a}\:\mathrm{60}{kg}\:{student}\:{to}\:{accelerate} \\ $$$${downwards}\:{at}\:\mathrm{9}.\mathrm{8}{m}/{s}^{\mathrm{2}} .{Calculate} \\ $$$${the}\:{upward}\:{acceleration}\:{of}\:{the} \\ $$$${earth}\:{resulting}\:{from}\:{the}\:{student}'{s} \\ $$$${gravitational}\:{reaction}\:{force}\:{actinv} \\ $$$${on}\:{the}\:{earth}. \\ $$
Answered by mrW1 last updated on 07/Dec/17
$$\frac{\mathrm{60}}{\mathrm{5}.\mathrm{98}×\mathrm{10}^{\mathrm{24}} }×\mathrm{9}.\mathrm{8}=\mathrm{9}.\mathrm{8}×\mathrm{10}^{−\mathrm{23}} \:{m}/{s}^{\mathrm{2}} \\ $$