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2 years ago

You throw a ball straight up. You are extra strong feeling today. It takes 11 seconds for the ball to come back down.

Physics

1 answer:

ollegr [7]2 years ago

5 0

Answer:

A. 148.23 m

B. 2.75 m/s

Explanation:

The following data were obtained from the question:

Time of flight (T) = 11 s

Maximum height (h) =?

Initial velocity (u) =?

Next, we shall determine the time taken for the ball to get to the maximum height. This can be obtained as follow:

Time of flight (T) = 11 s

Time (t) to reach the maximum height =.?

T = 2t

11 = 2t

Divide both side by 2

t = 11/2

t = 5.5 s

NOTE: Time to reach the maximum height is the same as the time taken for the ball to fall back to the plane of projection.

A. Determination of the maximum height to which the ball was thrown.

Time (t) to reach maximum height = 5.5 s

Acceleration due to gravity (g) = 9.8 m/s²

Maximum height (h) =?

h = ½gt²

h = ½ × 9.8 × 5.5²

h = 4.9 × 30.25

h = 148.23 m

B. Determination of the initial velocity.

Maximum height (h) reached = 148.23 m

Acceleration due to gravity (g) = 9.8 m/s²

Initial velocity (u) =?

u² = h/2g

u² = 148.23 / (2 × 9.8)

u² = 148.23 / 19.6

Take the square root of both side

u = √(148.23 / 19.6)

u = 2.75 m/s

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Explain the meaning and use of the following acronyms: HELIOS, Exo-FMS, HAZMAT, NIRSpec.

adelina 88 [10]

Answer:

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HAZMAT-Hazardous materials

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Explanation:

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1 year ago

A horizontal 2.00\ m2.00 m long, 5.00\ kg5.00 kg uniform beam that lies along the east-west direction is acted on by two forces.

Sunny_sXe [5.5K]

Answer: $240\ rad/s^2$

Explanation:

Given

Length of beam $l=2\ m$

mass of beam $m=5\ kg$

Two forces of equal intensity acted in the opposite direction, therefore, they create a torque of magnitude

$\tau =F\times l=200\times 2=400\ N.m$

Also, the beam starts rotating about its center

So, the moment of inertia of the beam is

$I=\dfrac{ml^2}{12}=\dfrac{5\times 2^2}{12}\\\\I=\dfrac{5}{3}\ kg.m^2$

Torque is the product of moment of inertia and angular acceleration

$\Rightarrow \tau=I\alpha\\\\\Rightarrow 400=\dfrac{5}{3}\times \alpha\\\\\Rightarrow \alpha =240\ rad/s^2$

7 0

3 years ago

3. (Solids, Liquids) have no definite shape, but definite volume.<br> A)Solids <br> B)Liquids

JulijaS [17]

Answer:

b liquids

Explanation:

this is because liquids take the shape of their container while solids stay solid and do not change shape and solids, liquids and gases all have definite volume.

7 0

3 years ago

Einstein and Lorentz, being avid tennis players, play a fast-paced game on a court where they stand 25.0 m from each other. Bein

Lerok [7]

Answer:

A) 199.78 J

B) 9.292x10^14 J

C) 4.2x10^7 m/s

D) 0.65 m

E) 1.13x10^-8 sec

D) 2.94x10^-9 sec

Explanation:

mass of ball = 0.0580 kg

If smashed at v = 83.0 m/s, KE is

KE = 0.5mv^2

= 0.5 x 0.0580 x 83.0^2

= 199.78 J

B) if returned at v = 1.79×10^8 m/s, KE will be

KE = 0.5mv^2

= 0.5 x 0.0580 x (1.79×10^8)^2

= 9.292x10^14 J

C) during Einstein's return, velocity of rabbit relative to players is

Vr = 2.21×108 m/s

Rabbit's velocity relative to ball = 2.21×10^8 - 1.79×10^8

= 4.2x10^7 m/s

D) the rabbit's speed approaches the speed of light so we consider relativistic effect. The rabbit's measured distance is

l = l°( 1 - v^2/c^2)

= 2.5(1 - 2.21/3)

= 2.5 x 0.26

= 0.65 m

E) according to the players, the time taken by the rabbit is

t = d/v = 2.5/ 2.21×10^8

= 1.13x10^-8 sec

F) the time for rabbit as measured by rabbit is relativistic

t = t°( 1 - v^2/c^2)

= 1.13x10^-8 (1 - 2.21/3)

= 1.13x10^-8 x 0.26

= 2.94x10^-9 sec

7 0

3 years ago

A small mirror is attached to a vertical wall, and it hangs a distance of 1.87 m above the floor. The mirror is facing due east,

Oksana_A [137]

Answer:

t = 1.62 h

Explanation:

A flat mirror fulfills the law of reflection where the incident angle is equal to the reflected angle.

θ_i = θ_r

If we use trigonometry to find the angles, the mirror is at a height of L = 1.87 m, and the reflected rays reach a distance x1 = 3.56 m

tan θ₁ = x₁ / L

tan θ₁ = $\frac{3.56}{1.87}$

θ₁ = tan⁻¹ 1.90

θ₁ = 62.29º

for the second case x₂ = 1.46 m

tan θ₂ = x₂ / L

θ₂ = tan⁻¹ $\frac{1.46}{1.87}$

θ₂ = 37.98º

the difference in degree traveled is

Δθ = θ₁- θ₂

Δθ = 62.29 - 37.98

Δθ = 24.31º

as in the exercise they indicate that every 15º there is an hour

t = 24.31º (1h / 15º)

t = 1.62 h

4 0

3 years ago