Joe runs 10 m north, 20 m south, 9m south, and then 15 m north. What is Joe's displacement?

I need help with #40 need answer and show me what you multiplied please

ale4655 [162]

(0.5)×(0squared)×(3)=(1.5j)

3 0

3 years ago

Imagine you had a bar of gold and decided to cut in half. You repeated this process until eventually you could no longer cut the

nydimaria [60]

This would prove that gold is an element. No matter how far down you
examine it, you never find any particles of anything except gold.

An example of a different case is salt.
-- Imagine you had a block of salt and decided to cut it in half.
-- If you repeated this process, then eventually, at some point, you'd have
a tiny particle of salt in front of you, just like before. BUT ...
-- Just as you were getting ready to cut this one in half, you'd notice that this
particle of salt is different. It's one atom of sodium stuck to one atom of chlorine,
and if you cut it in half, you would not have ANY salt. 

This would prove that salt is a compound, made of atoms of two or more elements.

3 0

4 years ago

Read 2 more answers

A spring with a spring constant of 165 N/m is attached to a 2.0 kg mass and set into motion.

marin [14]

Explanation:

We have,

Spring constant of the spring, k = 165 N/m

Mass, m = 2 kg

It is required to find the period of the mass-spring system. For the spring mass system, the period is given by :

$T=2\pi \sqrt{\dfrac{m}{k} }\\\\T=2\pi \sqrt{\dfrac{2}{165} }\\\\T=0.69\ s$

The frequency of vibration is reciprocal of its time period. So,

$f=\dfrac{1}{T}\\\\f=\dfrac{1}{0.69}\\\\f=1.44\ Hz$

So, the period of the mass-spring system is 0.69 s and frequency is 1.44 Hz.

3 0

3 years ago

Calculate the amount of heat (in kj) required to convert 74.6 g of water to steam at 100°c

Kryger [21]

You just need the energy of turning of water in to steam. Water is a little funny because once water gets to 100 degrees C, it stops changing in temperature whilst it all turns to steam. The amount of energy required to turn 1 gram of water into steam is 2257 Joules. We call this the latent heat of vaporisation. So to turn 74.6 grams of water to steam, you would need:

2257J/gram x 74.6g = 168,372.2 J = 168.4 kJ

(latent heat of vaporisation: 2257 J/gram)

7 0

3 years ago

What happens to the acceleration if you triple the force that you apply to the painting with your hand? (Use the values from the

8_murik_8 [283]

Answer:

2) when acceleration triples force triples, 3) a diagram with dynamic friction force in the opposite direction of movement of the car

4) a = 2.44 ft / s², 5) fr = 894.3 N

Explanation:

In this exercise you are asked to answer some short questions

2) Newton's second law is

F = m a

when acceleration triples force triples

3) Unfortunately, the diagrams are not shown, but the correct one is one where the axis of movement has a friction force in the opposite direction of movement, as well as indicating that the car slips, the friction coefficient of dynamic.

The correct answer is: a diagram with dynamic friction force in the opposite direction of movement of the car

4) let's use the scientific expressions

v = v₀ - a t

as the car stops v = 0

a = v₀ / t

let's reduce the magnitudes

v₀ = 40 mile / h ( $\frac{5280 ft}{1 mile}$ ) ( $\frac{1 h}{3600 s}$ ) = 58.667 ft / s

a = 58.667 / 24

a = 2.44 ft / s²

5) let's use Newton's second law

fr = m a

We must be careful not to mix the units, we will reduce the acceleration to the system Yes

a = 2.44 ft / s² (1 m / 3.28 ft) = 0.745 m / s²

fr = 1200 0.745

fr = 894.3 N

5 0

3 years ago