Answer:
150 m
Explanation:
Distance traveled during reaction time = .5 x 30 = 15 m
Actual distance during which there was deceleration = 60 - 15 = 45 m .
force x displacement = kinetic energy
F x s = 1/2 m v² ;
F x 45 = 1/2 m 30² = 450 m ----( 1 )
for second case
Fx S = 1/2 m 50² = 1250 m --------( 2 )
Dividing( 1 )and ( 2 )
S/45 = 1250 /450 = 125 / 45
S = 125 m
Add distance traveled in reaction time in second case = 50 x .5 = 25 m
total distance required = 25 + 125 = 150 m
explanation
1 = C
2 = A
3 = D
4 = E
5 = B
part 1
mass = ρ x V
mass = 1739 kg/m³ x 3.8 km³ = 6608.2 kg
PE (potential energy)= mgh
PE = 6608.2 kg x 9.81 x 403
PE = 2.61 x 10⁷ J
part 2
megaton of TNT (Mt) =4.2 x 10¹⁵ J
convert PE to Mt:
2.61 x 10⁷ J : 4.2 x 10¹⁵ J = 6.21 x 10⁻⁹ Mt
The element is iridium and it has 77 electrons
