Answer:
3500N
Explanation:
Given parameters:
Mass of driver = 50kg
Speed = 35m/s
Time = 0.5s
Unknown:
Average force the seat belt exerts on her = ?
Solution:
The average force the seat belt exerts on her can be deduced from Newton's second law of motion.
F = mass x acceleration
So;
F = mass x ![\frac{change in velocity }{time}](https://tex.z-dn.net/?f=%5Cfrac%7Bchange%20in%20velocity%20%7D%7Btime%7D)
F = 50 x
= 3500N
Answer:
Explanation:
To measure increase in length due to thermal expansion, the formula is
L₂ =L₁ ( 1 + α t ) where L₁ length increases to L₁ due to rise in temperature by t.
L₂ in both the case is same so
for aluminium
L₂ = 2.8 ( 1 + 23 X 10⁻⁶ t )
for steel
L₂ = 2.804 ( 1 + 12 X 10⁻⁶ t )
2.8 ( 1 + .000023t) = 2.804 ( 1 + .000012 t )
Solving this equation
t = 122C
Final temperature of both = 122 +20 = 142 C
Known :
v1 = 0 m/s
vt = 10 m/s
t = 4 s
Asked :
a = ...?
Answer :
a = (vt - v1)/t
= (10 - 0)/4
= 10/4
= 5/2
= <u>2 ½</u><u> </u><u>m/</u><u>s</u><u>²</u>
= <u>2</u><u>.</u><u>5</u><u> </u><u>m/</u><u>s</u><u>²</u>
<em>Hope </em><em>it </em><em>helpful </em><em>and </em><em>useful </em><em>:</em><em>)</em>