Newton's first law of motion says C

The cheetah, the fastest of land animals, can run a distance of 274 m in 8.65 s at its top speed. What is the cheetahs top speed

OverLord2011 [107]

Answer:

31.68 meters per second.

Explanation:

Speed is equals to Distance divided by Time, so, this means that speed is inversely proportional to time and directly proportional to distance.

Here, Distance is given which is 274 meters.

Time taken to cover the given distance is 8.65 seconds.

So, by putting the values of distance and time in the formula of speed we will get the top speed of Cheetah which is 31.68 meters per second.

8 0

3 years ago

Indiana Jones is in a temple searching for artifacts. He finds a gold sphere with a radius of 2 cm sitting on a pressure sensiti

Vlad1618 [11]

Answer:

Volume of Sand = 0.4 m³

Radius of Sand Sphere = 0.46 m

Explanation:

First we need to find the volume of gold sphere:

Vg = (4/3)πr³

where,

Vg = Volume of gold sphere = ?

r = radius of gold sphere = 2 cm = 0.02 m

Therefore,

Vg = (4/3)π(0.2 m)³

Vg = 0.0335 m³

Now, we find mass of the gold:

ρg = mg/Vg

where,

ρg = density of gold = 19300 kg/m³

mg = mass of gold = ?

Vg = Volume of gold sphere = 0.0335 m³

Therefore,

mg = (19300 kg/m³)(0.0335 m³)

mg = 646.75 kg

Now, the volume of sand required for equivalent mass of gold, will be given by:

ρs = mg/Vs

where,

ρs = density of sand = 1602 kg/m³

mg = mass of gold = 646.75 kg

Vs = Volume of sand = ?

Therefore,

1602 kg/m³ = 646.75 kg/Vs

Vs = (646.75 kg)/(1602 kg/m³)

Now, for the radius of sand sphere to give a volume of 0.4 m³, can be determined from the formula:

Vs = (4/3)πr³

0.4 m³ = (4/3)πr³

r³ = 3(0.4 m³)/4π

r³ = 0.095 m³

r = ∛(0.095 m³)

4 0

3 years ago

Suppose you toss a tennis ball upward.a) Does the kinetic energy of the ball increase or decrease as it moves higher?b) What hap

Lilit [14]

Answer:

a) No. The kinetic energy of the ball decreases.

b) The potential energy of the ball increases.

c) The ball would go half of the original distance.

Explanation:

a) The kinetic energy would be converted to potential energy as the ball goes higher. Since the total mechanical energy is conserved, the kinetic energy would decrease.

b) The potential energy of the ball would increase. Since the total mechanical energy of the ball is conserved, the ball would lose speed, and therefore kinetic energy. In order to compensate the loss of kinetic energy, the ball would gain potential energy as it goes higher.

c) The relation of the energy and mass is as follows:

$K = \frac{1}{2}mv^2\\U = mgh$

According to the energy conservation

$K_1 + U_1 = K_2 + U_2\\\frac{1}{2}mv^2 + 0 = 0 + mgh\\\frac{1}{2}v^2 = gh$

The maximum height that the ball reaches is proportional to the initial velocity. If the ball would be imparted with the same amount of energy, its final potential energy would be the same. However, in order to have the same potential energy (mgh), its height would be half of the original case.

$mgh = (2m)g(\frac{h}{2})$

7 0

3 years ago

A camcorder has a power rating of 10 watts. If the output voltage from its battery is 3 volts, what current does it use?

Gemiola [76]

The power is calculated using the following rule:
Power = voltage * current
We are given that:
power = 10 watts
voltage = 3 volts

Substitute with the givens in the above equation to get the value of the current as follows:
P = V*I
10 = 3*I
current (I) = 10/3 amperes

7 0

3 years ago

if a toaster oven uses 1000 J of electrical energy to produce 800 J of thermal energy, what is the percent efficiency of the toa

ArbitrLikvidat [17]

Answer:

80%

Explanation:

The thermal energy output by the oven is 800 J which is the useful energy that can be utilized for cooking.

The electrical energy input to the oven is 1000 J.

The efficiency of the oven =

(Useful energy output)/(Total energy input to the oven) x 100

$=\frac{800}{1000}\times 100= 80\%$

Hence, the efficiency of the oven is 80%.

3 0

4 years ago