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2 years ago

What does it mean when work is positive?

1 answer:

7 0

Both positive work and negative work have meaning: Positive work follows when the force has a component parallel to the displacement. Positive work adds energy to a system. Negative work follows when the force has a component opposite or against the displacement.

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Explain the correspondence that lets us easily translate between linear motion and rotational motion. What are the linear analog

RideAnS [48]

Explanation:

The linear analog of angle is angle itself.

The linear analog of angular velocity is linear velocity.

ω is angular velocity, therefore linear velocity is given by v

∴ for linear velocity, $v^{2} = u^{2}+2.a.S$

for angular velocity, $\omega_{f}^{2} = \omega _{i}^{2}+2.a.S$

The linear analog of angular acceleration is acceleration.

α is angular acceleration whereas as a is linear acceleration.

∴ for linear acceleration, v = u + a.t

for angular acceleration, $\omega_{f}= \omega _{i}+\alpha .t$

The linear analog of moment of inertia is mass.

I is moment of inertia and m is mass,

∴ for linear analog, F = m.a

for angular analog, τ - I.α

4 0

3 years ago

How can scientists study the inner structure of an atom?

Arturiano [62]

A microscope is one way

8 0

3 years ago

As a car drives with its tires rolling freely without any slippage, the type of friction acting between the tires and the road i

Darya [45]

<span>As a car drives with its tires rolling freely without any slippage, the type of friction acting between the tires and the road is kinetic friction.

We exert force to move the object from rest and in this case, static friction works. But, when the object comes in motion, then kinetic friction works. Here, since the car is driving without slipping means, kinetic friction acts on it. Its also called sliding or dynamic friction.</span>

5 0

3 years ago

You add 500 mL of water at 10°C to 100 mL of water at 70°C. What is the

Sphinxa [80]

Answer:

Option (c) : 20°C

Explanation:

$t(final) = \frac{w1 \times t1 + w2 \times t2}{w1 + w2}$

T(final) = 500* 10 + 100*70/600 = 20°C

4 0

3 years ago

A 0.05kg dart is thrown at and sticks into a 0.4 kg block hanging on a string. After the collision the block and dart swing in a

zloy xaker [14]

Answer:

v = 1.4 m /s

Explanation:

We shall apply law of conservation of mechanical energy

The kinetic energy of dart and block is converted into potential energy of both dart and block .

1 /2 (m+M) v² = ( m +M) gH

.5 x v² = 9.8 x .1

= v² = 1.96

v = 1.4

v = 1.4 m /s

6 0

3 years ago