I need help please and thanks

At a certain instant, the speedometer of the car indicates 80 km/h.

Scorpion4ik [409]

Answer:

It tells the speed of car. At this time the speed of car is 80km/h , means if the car runs constantly at this speed then it will cover 80 kilometres in 1 hour.

. 

.

${\bold{\red{HOPE\:IT\:HELPS!}}}$

$\color{yellow}\boxed{\colorbox{black}{MARK\: BRAINLIEST!❤}}$

4 0

2 years ago

Which waves require a material medium for transmission? a.) light waves b.) radio waves c.) sound waves d.) microwaves

shepuryov [24]

Answer:

mechanical waves require a medium

5 0

3 years ago

Which of these are point sources of water pollution?

bija089 [108]

Gas stations or sewage treatment facility

4 0

3 years ago

Which of the following exerts the strongest gravitational force on Earth? (Need help)

jarptica [38.1K]

Answer:

Moon

Explanation:

although the moon is by far the smallest mass of the listed bodies, it is also by far the closest.

6 0

3 years ago

Calculate the percentage increase in length of a wire of diameter 2.2 mm stretched by a load of

vesna_86 [32]

Answer:

0.21%

Explanation:

We are given;

Mass; m = 100 kg

Diameter; d = 2.2 mm = 2.2 × 10^(-3) m

Young's modulus; E = 12.5 x 10^(10) N/m².

Formula for area is;

A = πd²/4

A = (π/4) x (2.2 x 10^(-3))²

A = 3.8 x 10^(-6) m²

Force; F = mg

g is acceleration due to gravity and has a constant value of 9.8 m/s²

F = 100 × 9.8

F = 980 N

Formula for young's modulus is;

E = Stress/strain

Formula for stress = F/A

Formula for strain = ΔL/L

Thus;

E = (F/A)/(ΔL/L)

Making ΔL/L the subject, we have;

ΔL/L = (F/A)/E

Plugging in the relevant values;

ΔL/L = 980/(3.8 x 10^(-6) × 12.5 × 10^(10))

ΔL/L = 0.0021

Then percentage increase in length of a wire = 0.0021 × 100% = 0.21%

8 0

3 years ago