De ce nu putem masura o bandă

you cnat measure a band because they come in all shapes and sizes they can be streched or to wide.

Explanation: the only way which is sometimes innacurate is if you cut the rubber band and measure it but you still cant measure it

Explanation:

Range R = 7 m

angle of projection θ = 40⁰

u² sin2θ / g = R where u is velocity of throw.

u² sin 80 / g = 7

u² = 69.71

u = 8.35 m/s

horizontal velocity = u cos 40 = 8.35 cos 40

= 6.4 m /s

vertical velocity = u sin 40 = 8.35 sin40

= 5.37 m /s

Maximum height :-

v² = u² - 2gh , u is initial vertical component of throw.

0 = 5.37² - 2 x 9.8 x h

h = 1.47 m

Time to reach max height :--

v = u - gt

o = 5.37 - 9.8 t

t = .55 s