What evidence do scientists have that earth has been hit by large objects like asteroids in the past

Biological factor related to antisocial personality disorder is

dusya [7]

Schizotypal personality disorder and borderline personality disorder

4 0

3 years ago

Find an expression for the acceleration a of the red block after it is released. use mr for the mass of the red block, mg for th

Drupady [299]

<span>Assuming pulley is frictionless. Let the tension be ‘T’. See equation below.</span>

6 0

3 years ago

Read 2 more answers

A box is pulled 6 meters across the ground at a constant velocity by a horizontally applied force of 50 newtons. At the same tim

Vikentia [17]

Answer:

(a) Friction force = 50 N

(b) Work done by friction = 300 j

(c) Net work done = 0 j

Explanation:

We have given that the box is pulled by 6 meter so d = 6 m

Force applied on the box F = 60 N

We have have given that velocity is constant so acceleration will be zero

So to applied force will be utilized in balancing the friction force

So friction force $F_{friction}=50N$

Work done by friction force $W_{friction}=F_{friction}\times d=50\times 6=300j$

Work done by applied force $W=F\times d=50\times 6=300j$

So net work done = 300-300 = 0 j

7 0

3 years ago

A fat person weighing 80 Kg falls on a concrete floor from 2m. If whole of the mechanical energy is converted into heat energy,

sasho [114]

Answer:

The heat produced is 1568 J

Explanation:

The given parameters are;

The mass of the person, m = 80 kg

The height from which the person falls, h = 2 m

Mechanical Energy, ME = Potential Energy, PE + Kinetic Energy, KE

At the height, from where the person falls, the initial velocity of the person = 0 m/s

Therefore;

The initial kinetic energy, K.E. = 1/2·m·v² = 1/2 × 80 kg × (0 m/s)² = 0 J

From which we have;

The Mechanical Energy, M.E. = The initial Potential Energy, P.E. + 0 J

∴ The Mechanical Energy, M.E. = The initial Potential Energy, P.E.

The initial Potential Energy, P.E. = m·g·h

Where;

m = The mass of the person

g = The acceleration due to gravity ≈ 9.8 m/s²

∴ The initial Potential Energy, P.E. = 80 kg × 9.8 m/s² × 2 m = 1568 J

The Mechanical Energy, M.E. = The initial Potential Energy, P.E. = 1568 J

The whole mechanical energy is converted into heat energy, therefore, we have;

The Mechanical Energy, M.E. = The heat energy = 1568 J

The heat produced = The heat energy = 1568 J.

4 0

2 years ago

Why is it impossible to build a machine that produces more energy than it uses?

Irina18 [472]

Because then it could mess up the machine with to much energy

8 0

3 years ago