Ask question

Ask question

All categories

3 years ago

11

A block of mass of 10kg is being pushed on a tabletop downwards by a force of 200N. There is no acceleration in the problem. Cal

culate the normal force being exerted on the block.

1 answer:

lord [1]3 years ago

7 0

F = M*A

200N*10KG is 2000 newtons

so 2000 newton's is the normal force that is being exerted on the block

You might be interested in

How much force is needed to accelerate a 68 kilogram skier at a rate of 1.2m/sec

xxMikexx [17]

Let's use Newton's 2nd law of motion:

Force = (mass) x (acceleration)

Force = (68 kg) x (1.2 m/s²) = 81.6 newtons .

8 0

3 years ago

Read 2 more answers

A rubber balloon is rubbed with a PVC pipe and the rubber balloon becomes positively charged. Why is this? a) Because the rubber

pentagon [3]

Answer:

d)

Explanation:

Electrons are lost or gained when the ballon is rubbed with a PVC. As the rubber ballon lost electrons, it will have more protons, hence the positive charge. (More protons than electrons in the ballon).

4 0

3 years ago

What order shows increasing frequency for gamma rays, microwaves, visible light, and X-rays?

sergejj [24]

Answer:

Person above me is right, it's B: microwaves, visible light, X-rays, gamma rays

Explanation:

6 0

3 years ago

The following table lists the work functions of a few common metals, measured in electron volts. Metal Φ(eV) Cesium 1.9 Potassiu

Citrus2011 [14]

A. Lithium

The equation for the photoelectric effect is:

$E=\phi + K$

where

$E=\frac{hc}{\lambda}$ is the energy of the incident light, with h being the Planck constant, c being the speed of light, and $\lambda$ being the wavelength

$\phi$ is the work function of the metal (the minimum energy needed to extract one photoelectron from the surface of the metal)

K is the maximum kinetic energy of the photoelectron

In this problem, we have

$\lambda=190 nm=1.9\cdot 10^{-7}m$ , so the energy of the incident light is

$E=\frac{hc}{\lambda}=\frac{(6.63\cdot 10^{-34}Js)(3\cdot 10^8 m/s)}{1.9\cdot 10^{-7} m}=1.05\cdot 10^{-18}J$

Converting in electronvolts,

$E=\frac{1.05\cdot 10^{-18}J}{1.6\cdot 10^{-19} J/eV}=6.5 eV$

Since the electrons are emitted from the surface with a maximum kinetic energy of

K = 4.0 eV

The work function of this metal is

$\phi = E-K=6.5 eV-4.0 eV=2.5 eV$

So, the metal is Lithium.

B. cesium, potassium, sodium

The wavelength of green light is

$\lambda=510 nm=5.1\cdot 10^{-7} m$

So its energy is

$E=\frac{hc}{\lambda}=\frac{(6.63\cdot 10^{-34}Js)(3\cdot 10^8 m/s)}{5.1\cdot 10^{-7} m}=3.9\cdot 10^{-19}J$

Converting in electronvolts,

$E=\frac{3.9\cdot 10^{-19}J}{1.6\cdot 10^{-19} J/eV}=2.4 eV$

So, all the metals that have work function smaller than this value will be able to emit photoelectrons, so:

Cesium

Potassium

Sodium

C. 4.9 eV

In this case, we have

- Copper work function: $\phi = 4.5 eV$

- Maximum kinetic energy of the emitted electrons: K = 2.7 eV

So, the energy of the incident light is

$E=\phi+K=4.5 eV+2.7 eV=7.2 eV$

Then the copper is replaced with sodium, which has work function of

$\phi = 2.3 eV$

So, if the same light shine on sodium, then the maximum kinetic energy of the emitted electrons will be

$K=E-\phi = 7.2 eV-2.3 eV=4.9 eV$

7 0

4 years ago

The equation that relates two poles to the force between them and their separation is the ____ square law.

Ivenika [448]

A-exponential
You welcome

4 0

3 years ago