All categories

3 years ago

I throw a ball off the edge of a 15.0m cliff. If I threw it horizontally at 8.0 m/s, how much time did it take to fall?

1 answer:

3 0

Just ignore the horizontal component

if you have a vertical displacement of 15m, 0ms^1 initial velocity, end velocity is ignored, we know the acceleration due to gravity as 9.81ms^2 so we can work out the time using SUVAT

S=15
U=0
V=?
A=9.81
T=?

S=UT + 0.5 AT^2

UT=0

therefore,

S=0.5AT^2

rearrange to:

T=SQR (2S/A)

T = 1.75 seconds

You might be interested in

The moon is made up mostly of _______, similar to minerals on earth

yKpoI14uk [10]

silicates for the answer

8 0

3 years ago

A car traveling at 37m/s starts to decelerate steadily. It comes to a complete stop in 15 seconds. What is it’s acceleration

LuckyWell [14K]

Answer

The acceleration is

$a=-2.5ms^{-2}$ to the nearest tenth

Explanation

Since the car was travelling at $37ms^{-1}$ before it starts to decelerate, the initial velocity is

$u=37ms^{-1}$ .

The final velocity is $v=0ms^{-1}$ , because the car came to a stop.

The time taken is $t=15s$ .

Using the Newton's equation of linear motion,

$v=u +at$ , we find the acceleration by substituting the known values.

This implies that,

$0=37 +a(15)$

This gives us,

$0-37=15a$

$\Rightarrow -37=15a$

We divide both sides by 15 to get,

$a=-\frac{37}{15}ms^{-2}$

$a=-2.46667ms^{-2}$

6 0

3 years ago

You work at a retail store. Recently, paychecks have had errors and there have been many employee complaints. You have been assi

Nata [24]

Answer:

C,B,A

Explanation:

5 0

3 years ago

Read 2 more answers

If you are driving 72 km/h along a straight road and you look to the side for 4.0 s, how far do you travel during this inattenti

Ann [662]

We know that speed equals distance between time. Therefore to find the distance we have that d = V * t. Substituting the values d = (72 Km / h) * (1h / 3600s) * (4.0 s) = 0.08Km.Therefore during this inattentive period traveled a distance of 0.08Km

8 0

3 years ago

A string under a tension of 36 N is used to whirl a rock in a horizontal circle of radius 3.6 m at a speed of 16.12 m/s. The str

ExtremeBDS [4]

Answer:

6010.457N

Explanation:

Centripetal acceleration = a= V²/R

At a radius of 3.6m and velocity of 16.12m/s,

Acceleration is

a = 16.12²/ 3.6 = 72.182 m/s²

Force = Mass (m) * Acceleration (a)

36 = m * 72.182

m = 36/72.182

At breaking point

Radius = 0.468 m and Velocity = 75.1 m/s

a = V²/R = 75.1²/0.468

a = 12051.3 m/s

F = Mass(m) * Acceleration (a)

F = m * 12051.3

m = F/ 12051.3

Settings the ratio of mass equal

m = m

=> 36/72.182 = F/12051.3

F = 12051.3 * 36/72.182

F = 6010.457N

3 0

3 years ago