What must a scientist do in order to develop a testable hypothesis?

Solar panels allow us to harness ___________ energy and convert it to __________ energy to heat water.

vichka [17]

Solar energy
thernal energy

3 0

4 years ago

Larger animals use proportionately less energy than smaller animals; that is, it takes less energy per kg to power an elephant t

marin [14]

Answer:

Part a)

$Q = 952 cal/day$

Part b)

$P = 46 Watt$

Part c)

$\Delta P = 54 W$

Explanation:

As we know that 5000 kg African elephant requires 70,000 Cal for basic needs per day

so we will have

$m = 5000 kg$

$Q = 70,000 Cal$

so we have energy required per kg

$E = \frac{70,000}{5000}$

$E = 14 cal/kg$

Part a)

now we know that per kg the energy required will be same

so we have mass of the human is 68 kg

so energy required per day is given as

$Q = 68 \times 14$

$Q = 952 cal/day$

Part b)

Resting power is the rate of energy in Joule required per sec

so it is given as

$P = \frac{952 \times 4186}{24\times 3600}$

$P = 46 Watt$

Part c)

resting power given in the book is

$P' = 100 W$

so this is less than the power given

$\Delta P = 100 - 46$

$\Delta P = 54 W$

6 0

3 years ago

What do the magnets in a computer hard drive and in the strip on a credit

Sonja [21]

Answer:

they store information

Explanation:

Information are encoded on the magnetic part of a hard drive and the strip of a credit card.

On the drive, series of magnetic fields are used to encode information.
The data is stored in form of zeros and ones.
A credit card has a magnetic strip where information is encoded.
The stripe provides a readability function for electronic devices.

5 0

3 years ago

Initially at rest a single-stage rocket is launched vertically from the ground. The rocket’s thrust overcomes gravity and provid

Lelechka [254]

Answer:

Explanation:

Let a be the acceleration of launch. In 10 seconds , Distance gone up in 10 seconds

s = 1/2at²

= .5 x a x 100

=50a

Velocity after 10 s

u = at = 10a

Now 50a distance in downward direction is travelled in 20 s with initial velocity 10a in upward direction.

s = ut + 1/2 gt²

50a = -10ax20 + .5 x 10x400

250a = 2000

a = 8 m s⁻² .

Velocity after 10 s

= at = 80 m/s

further height reached with this speed under free fall

h = v² / 2g

= 80 x 80 / 2 x 10

= 320 m

height achieved under acceleration

= 50a

= 50 x 8 = 400m

Total height

= 320 + 400= 720 m

velocity after falling from 720 m

v² = 2gh = 2 x10 x 720

v = 120 m/s

7 0

3 years ago

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answer A vertical spring stretches 3.4 cm when a 8-g object is hung from it. The object is replaced with a block of mass 26 g th

victus00 [196]

Answer:

0.695s

Explanation:

From Hooke's law, the restoring force is given has

F = -ky .......1

Where F is the force, y is the spring displacement and k force constant of the spring.

Also recall,

F=mg ............ 2

Where m is the mass of object, g is the acceleration due to gravity.

Equating 1 and 2

Ky = mg

Given that g=9.8m/s2 , y is 3.4cm and g is 8g

K×3.4/100m =8/1000kg × 9.8m/s2

K= ( 0.008kg × 9.8m/s2 ) ÷ 0.034

K= 0.0784÷0.035

K=2.24N/m

Mass ofvthe second object is 25g =0.025kg

Period of oscillation T

T=2π√m/k

T=2×3.142√0.025/2.24

T=6.284√0.0111

T=0.659seconds

8 0

3 years ago

Read 2 more answers