All categories

3 years ago

Can someone please help? Thank u!

Physics

1 answer:

Snowcat [4.5K]3 years ago

7 0

Answer:

B. 7.5 m/s^2

Explanation:

To find acceleration you need to subtract the final velocity by the starting velocity then divide that by the time

a= v-v/t

a= 60-0/8

a= 60/8

a=7.5 m/s^2

You might be interested in

Plz help<br>I need it fast<br>

Rufina [12.5K]

Answer:

perpendicular to

Explanation:

it means perpendicular to .....should u come across something like this / / , this one means parallel to .....

7 0

3 years ago

Read 2 more answers

System uses 49J of energy to do work in the change of internal energy is 58 j. how much heat was added to the system?

Alika [10]

Answer:

107

Explanation:

6 0

3 years ago

A bodybuilder deadlifts a 215 kg weight to a height of 0.90 m above the ground. If he deadlifts this weight 10 times in a span o

wariber [46]

A bodybuilder deadlifts 215 kg to a height of 0.90 m. If he deadlifts this weight 10 times in 45 s, the power exerted is 421 W (b.)

<h3>What is power?</h3>

In physics, power (P) is the work (W) done over a period of time.

Step 1. Calculate the work done by the bodybuilder each time.

The bodybuilder lifts a 215 kg (m) weight to a height of 0.90 m (h). Being the gravity (g) of 9.81 m/s², we can calculate the work done in each lift using the following expression.

W = m × g × h = 215 kg × 9.81 m/s² × 0.90 m = 1.9 × 10³ N

Step 2. Calculate the work done by the bodybuilder over 10 times.

W = 10 × 1.9 × 10³ N = 1.9 × 10⁴ N

Step 3. Calculate the power exerted by the bodybuilder.

The bodybuilder does a work of 1.9 × 10⁴ N in a 45-s span.

P = 1.9 × 10⁴ N/45 s = 421 W

A bodybuilder deadlifts 215 kg to a height of 0.90 m. If he deadlifts this weight 10 times in 45 s, the power exerted is 421 W (b.)

Learn more about power here: brainly.com/question/911620

#SPJ1

4 0

2 years ago

An egg is dropped from a building that is 61 m high.

Allisa [31]

Answer:

Initial Velocity = 0 m/s

Final Velocity = 34.6 m/s

time = 3.5 s

Explanation:

The initial velocity must be zero since, the egg must be at rest initially, before dropping.

<u>Initial Velocity = 0 m/s</u>

Now, for time we use 2nd equation of motion:

h = Vi t + (1/2)gt²

where,

h = Height = 61 m

Vi = Initial Velocity = 0 m/s

g = 9.8 m/s²

t =time = ?

Therefore,

61 m = (0 m/s)(t) + (1/2)(9.8 m/s²)t²

t² = (61 m)(2)/(9.8 m/s²)

t = √(12.45 s²)

Now, for final velocity we will use 1st equation of motion:

Vf = Vi + gt

Vf = 0 m/s + (9.8 m/s²)(3.5 s)

Vf = 34.6 m/s

3 0

3 years ago

In a physics laboratory experiment, a coil with 250 turns enclosing an area of 10.5 cm2 is rotated during the time interval 3.10

olchik [2.2K]

I guess the problem is asking for the induced emf in the coil.

Faraday-Neumann-Lenz states that the induced emf in a coil is given by:
$\epsilon = -N \frac{\Delta \Phi}{\Delta t}$
where
N is the number of turns in the coil
$\Delta \Phi$ is the variation of magnetic flux through the coil
$\Delta t$ is the time interval

The coil is initially perpendicular to the Earth's magnetic field, so the initial flux through it is given by the product between the magnetic field strength and the area of the coil:
$\Phi_i = BA=(5.30 \cdot 10^{-5}T)(10.5 \cdot 10^{-4} m^2)=5.57 \cdot 10^{-8} Wb$
At the end of the time interval, the coil is parallel to the field, so the final flux is zero:
$\Phi_f = 0$

Therefore, we can calculate now the induced emf by using the first formula:
$\epsilon = -N \frac{\Delta \Phi}{\Delta t}=- (250) \frac{5.57 \cdot 10^{-8} Wb - 0}{3.10 \cdot 10^{-2} s} = -4.5 \cdot 10^{-4} V$

7 0

4 years ago