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4 years ago

PLZ HELP ME i don’t get this

Physics

1 answer:

Scorpion4ik [409]4 years ago

4 0

Explanation:

(i) Height of tree, h = 4 m

Mass of Ninja, m = 30 kg

The gravitational potential energy on the top branch of the tree is given by :

$P=mgh$

g is acceleration due to gravity

$P=30\ kg\times 9.8\ m/s^2\times 4\ m\\\\P=1176\ J$

(ii) If he were at a height of 2 meters from the ground, its potential energy will be :

$P=mgh$

g is acceleration due to gravity

$P=30\ kg\times 9.8\ m/s^2\times 2\ m\\\\P=588\ J$

Therefore, this is the required explanation.

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A force of 350 N causes a body to move with an acceleration of 10 m/s2. What's the mass of the body?

Dafna1 [17]

Answer:

35 kg

Explanation: Newton's Second Law of Motion reinterpreted as $M=\frac{f}{a}$ or $M=\frac{350}{35}$

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3 years ago

Neutrons can change the charge of an atom<br><br> True<br> False

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Answer:

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3 years ago

To test the performance of its tires, a car

VLD [36.1K]

Answer:

0.45

Explanation:

Sum of forces in the y direction:

∑F = ma

N − mg = 0

N = mg

There are friction forces in two directions: centripetal and tangential. The centripetal acceleration is:

ac = v² / r

ac = (31 m/s)² / 333 m

ac = 2.89 m/s²

The total acceleration is:

a = √(ac² + at²)

a = √((2.89 m/s²)² + (3.32 m/s²)²)

a = 4.40 m/s²

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∑F = ma

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μ = 0.45

5 0

4 years ago

One strategy in a snowball fight is to throw a snowball at a high angle over level ground. While your opponent is watching the f

Andreas93 [3]

Answer:

Part a)

$\theta_2 = 15 degree$

Part b)

$\Delta t = 2.88 s$

Explanation:

Part a)

In order to have same range for same initial speed we can say

$R_1 = R_2$

$\frac{v^2 sin2\theta_1}{g} = \frac{v^2 sin2\theta_2}{g}$

so after comparing above we will have

$\theta_1 = 90 - \theta$

so we have

$75 = 90 - \theta_2$

$\theta_2 = 15 degree$

Part b)

Time of flight for the first ball is given as

$T_1 = \frac{2vsin\theta}{g}$

$T_1 = \frac{2(20)sin75}{9.81}$

$T_1 = 3.94 s$

Now for other angle of projection time is given as

$T_2 = \frac{2(20)sin15}{9.81}$

$T_2 = 1.05 s$

So here the time lag between two is given as

$\Delta t = T_1 - T_2$

$\Delta t = 3.94 - 1.05$

$\Delta t = 2.88 s$

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3 years ago

The distance between Earth and Mars is 225 million km. When converted using the conversion factor 1 AU = 1.5 × 108 km, the dista

noname [10]

To convert km to AU, we divide 225,000,000 km by the factor of 1.5 x 10^8 = 150,000,000 km. This gives us 225,000,000 / 150,000,000 = 1.5 AU. Therefore, the distance between Earth and Mars in AU is 1.5 AU.
The AU is not equivalent to a light-year. A light-year is equivalent to around 9.5 x 10^12 kilometers.

4 0

4 years ago