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3 years ago

11

You want to calculate how long it takes a ball to fall to the ground from a height of 20 m. Which equation can you use to calcul

ate the time? (Assume no air resistance.)

1 answer:

fomenos3 years ago

8 0

Answer:it’s B.

Because it’s said in the fhoto

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A coyote can locate a sound source with good accuracy by comparing the arrival times of a sound wave at its two ears. Suppose a

il63 [147K]

Answer:

0.0000109261200583 s

0.0109261200583

Explanation:

$d_2$ = Distance from right ear = 3 m

s = Distance between ears = 15 cm

v = Speed of sound in air = 343 m/s

Distance between the left ear and the bird

$d_1=\sqrt{s^2+d_2^2}\\\Rightarrow d_1=\sqrt{0.15^2+3^2}\\\Rightarrow d_1=3.00374765918\ m=3.004\ m$

Time

$t=\dfrac{Distance}{Speed}$

Time difference would be

$\Delta T=\dfrac{d_1}{v}-\dfrac{d_2}{v}\\\Rightarrow \Delta T=\dfrac{3.00374765918}{343}-\dfrac{3}{343}\\\Rightarrow \Delta T=0.0000109261200583\ s$

The time difference is 0.0000109261200583 s

Time period is given by

$T=\dfrac{1}{f}\\\Rightarrow T=\dfrac{1}{1000}\\\Rightarrow T=10^{-3}\ s$

The ratio is

$\dfrac{\Delta T}{T}=\dfrac{0.0000109261200583}{10^{-3}}\\\Rightarrow \dfrac{\Delta T}{T}=0.0109261200583$

The ratio is 0.0109261200583

7 0

2 years ago

A car battery has a rating of 250 ampere-hours. This rating is one indication of the total charge that the battery can provide t

Serga [27]

Answer:

Total charge provided by the battery could be 900000 C.

Maximum current provided by the battery for 37 minutes could be 405.405 A

Explanation:

Rating= 250 A-h

a. Total charge:

$Rating=Q/t\\Q=Rating.t\\$

Suppose t=1h

$Q=250 A(1h)\\Q=250 A(3600 sec)\\Q= 900000 A.sec$

We konw that $Ampere=\frac{Coulomb}{sec}$ , replacing:

$Q=900000(\frac{Coulomb}{sec})(sec)\\Q=900000 Coulomb$

Total charge provided by the battery could be 900000 C.

b. Maximum current for 37 minutes

$I=\frac{Q}{t} \\I=\frac{900000 C}{37*60 sec}\\I=405.405 A$

Maximum current provided by the battery for 37 minutes could be 405.405 A

4 0

2 years ago

A dog is 10 m from a cat, whose speeds are 6 and 5 m / s, respectively. What time does the dog require to catch the cat?

scoray [572]

Answer:

10 seconds

Explanation:

because the cat is moving one m/s slower than the dog, the dog has a relative speed of 1 m/s. 10 meters would take 10 seconds for the dog to cover

4 0

3 years ago

An occupant of a car can survive a crash if the deceleration during the crash is less than 30 g. Calculate the force on a 64 kg

forsale [732]

The force on a 64 k person decelerating on that rate would be :

F = ma

F = 64 kg x 30 x 9.8

= 18816 N

Hope this helps

6 0

3 years ago

Explain the Construction of the mercury barometer

boyakko [2]

Answer:

The basic construction, unchanged since Torricelli's experiment in 1643, is a glass tube about three feet long, closed at one end, filled with mercury, and inverted with the open end immersed in a cistern of mercury.

6 0

2 years ago