Answer to Question #142148 in Classical Mechanics for Sridhar

Question

A ball is thrown vertically upwards with an initial velocity u reaches maximum height in 5 sec.The ratio of distance travelled by the ball in the second and seventh second is? ( g=10m/s²)

Answer 1

$V= V_0-gt; \text{for }t=5 \ V=0$

$V_0= gt= 50$

$S(t) = V_0t-\frac{gt^2}{2}$

$S(2)=50*2-\frac{10*2^2}{2}=80$

$S(7)=50*7 -\frac{10*7^2}{2}=$ 105

$\frac{S(2)}{S(7)}=\frac{80}{105}=\frac{16}{21}$

Answer:$\ \frac{16}{21}$