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3 years ago

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A student throws a rock horizontally off a 5.0 m tall building. The rock's initial speed is 6.0 m/s. How long will it take the r

ock to reach the ground? Air resistance is negligible.'

2 answers:

Archy [21]3 years ago

5 0

Answer:

The time taken by the rock to reach the ground is 0.569 seconds.

Explanation:

Given that,

A student throws a rock horizontally off a 5.0 m tall building, s = 5 m

The initial speed of the rock, u = 6 m/s

We need to find the time taken by the rock to reach the ground. Using second equation of motion to find it. We get :

$s=ut+\dfrac{1}{2}gt^2\\\\5=6t+\dfrac{1}{2}\times 9.8t^2\\\\t=0.569\ seconds$

So, the time taken by the rock to reach the ground is 0.569 seconds. Hence, this is the required solution.

trapecia [35]3 years ago

5 0

Answer:

The rock to reach the ground in 0.569 sec.

Explanation:

Given that,

Height = 5.0 m

Speed = 6.0 m/s

A student throws a rock horizontally off a 0.5 m tall building.

This is the distance.

So, s = 0.5 m

We need to calculate the time

Using equation of motion

$s=ut+\dfrac{1}{2}gt^2$

Where, s = distance

t = time

g = acceleration due to gravity

Put the value into the formula

$5.0=6.0\times t+0.5\times9.8t^2$

$4.9t^2+6.0 t-5.0 =0$

$t = 0.569\ sec$

Neglect the negative value.

Hence, The rock to reach the ground in 0.569 sec.

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Explanation:

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Solution:

The weight of an object is the force of gravity acting on the object;

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Acceleration due to gravity = 9.8m/s²

Now insert the parameters and solve;

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A person weighing 785 Newtons on the surface of the Earth would weigh 47 Newtons on the surface of Pluto. What is the magnitude of the gravitational acceleration on the surface of Pluto?

1.7 m/s²

0.59 m/s²

0.29 m/s²

9.8 m/s²

Given parameters:

Weight on Earth = 785N

Weight on Pluto = 47N

Unknown:

Acceleration due to gravity on Pluto = ?

Solution

The mass of the body both on Earth and Pluto is the same.

Weight = mass x acceleration due to gravity

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mass = $\frac{785}{9.8}$ = 80.1kg

So;

Acceleration due to gravity on Pluto = $\frac{Weight on Pluto}{mass }$

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2 years ago

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kenny6666 [7]

Answer:

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2 years ago

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Varvara68 [4.7K]

Answer:

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Explanation:

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1 kg=1000g

Mass of block=M=3 kg

d=0.086 m

Total mass =M+m=3+0.015=3.015 kg

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$\frac{1}{2}(m+M)^2V^2=(m+M)gh$

Using g= $9.8m/s^2$

Substitute the values

$\frac{1}{2}(3.015)V^2=3.015\times 9.8\times 0.086$

$V^2=\frac{2\times 3.015\times 9.8\times 0.086}{3.015}$

$V=\sqrt{2\times 3.015\times 9.8\times 0.086}}$

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Velocity after collision=V=1.3 m/s

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$mv+Mv'=(m+M)V$

Using the formula

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3 years ago

When you take your 1900-kg car out for a spin, you go around a corner of radius 55 m with a speed of 15 m/s. The coefficient of

pentagon [3]

Answer:

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Explanation:

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Now which direction is the static friction, assume that it is pointing inward so

Fc=Fs=mv²/r=1900*15²/55=427500/55=7772.72N

Since the car is not skidding we do not have kinetic friction so there can only be static friction. One reason we do not use μFn is because that is the formula for maximum static friction, and the problem does not state there is maximum static friction.

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2 years ago

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Sidana [21]

Answer:

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How many times stronger than gravity is this force? 2.79 x 10⁴ g.

Explanation:

given information:

s = 220 m

final speed, vf = 10.97 km/s = 10970 m/s

g = 9.8 m/s²

he unrealistically large acceleration experienced by the space travelers during their launch

vf² = v₀²+2as, v₀ = 0

vf² = 2as

a =vf²/2s

= (10970)²/(2x220)

= 2.7 x 10⁵ m/s²

Compare your answer with the free-fall acceleration

a/g = 2.7 x 10⁵/9.8

a/g = 2.79 x 10⁴

a = 2.79 x 10⁴ g

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2 years ago