I need help with something

What is the speed of a car that travels 150km in 3.00 hrs?

Leto [7]

The answer is <span>50 km/hr. </span>

8 0

4 years ago

Stephanie goes on a giraffe safari in Africa. She travels 8 km north, then 3 km west and then 2 km south.

pashok25 [27]

Answer:

distance =13km , displacement=3km

Explanation:

north south does not affect displacement

5 0

3 years ago

A rock falls from a tower that is 320 feet high. As it is falling, its height is given by the formula h equals 320 minus 16 t s

RSB [31]

Answer:

a. 4.5secs

Explanation:

From the question, the equation describing the height is given by

$h(t)=320-16t^{2}\\$

at the point when the rock hit the ground, the height,h will be zero.

Hence we can have

$h(t)=320-16t^{2}\\\\at h(t)=0\\0=320-16t^{2}\\hence \\320=16t^{2}\\t^{2}=\frac{320}{16}\\ t^{2}=20\\t=\sqrt{20}\\ t=4.47secs\\t=4.5sec\\$

hence the rock will hit the ground in 4.5secs

4 0

4 years ago

If the mass of block B is 2kg, the gravitational force exerted on block B is most nearly which of the following?

Katen [24]

Answer:

20 N.

Explanation:

The following data were obtained from the question:

Mass of block B (m) = 2 Kg

Acceleration due to gravity (g) = 10 m/s²

Gravitational force (F) =..?

Force is simply defined as the product of mass and acceleration i.e

Force = mass (m) × acceleration (a)

F = ma

Thus, we can say that the gravitational force on block B will be the product of the mass of block B and acceleration due to gravity i.e

Gravitational force (F) = mass of block B (m) × acceleration due to gravity (g)

F = mg

Mass of block B (m) = 2 Kg

Acceleration due to gravity (g) = 10 m/s²

Gravitational force (F) =..?

F = mg

F = 2 × 10

F = 20 N

The, the gravitational force exerted on block B is 20 N

6 0

3 years ago

A mass of 2 kg is attached to a spring and placed on a horizontal surface. The spring has a spring constant of 20 N/m, and the s

Sergio [31]

The speed of the mass : <em><u>v = 0.316 m/s</u></em>

<h3>Further explanation</h3>

The energy used to press a spring is included as the potential energy

Can be formulated:

$\displaystyle E_p=\frac{1}{2}kx^2$

Ep= potential energy

k = spring constant

x = change in spring length

If the spring is released from its pressure, this potential energy will turn into kinetic energy

so applies the law of conservation of mechanical energy (Em)

Ek = Ep

A mass of 2 kg is attached to a spring, a spring constant of 20 N/m, and the spring is compressed 0.1 m past its natural length.

m = 2 kg

k = 20 N/m

x = 0.1 m

$\displaystyle Ep=Ek\\\\\frac{1}{2}kx^2=\frac{1}{2}mv^2\\\\kx^2=mv^2\\\\20\times0.1^2=2\times v^2\\\\v^2=0.1\\\\v=\sqrt{0.1}\\\\v=0.316~m/s$

<h3>Learn more</h3>

Hooke's law

brainly.com/question/2648431

Keywords : spring,mass, spring constant,compressed position

5 0

3 years ago