Can somebody help me on this mcq question?

How to find the gradient of a velocity time graph

Sidana [21]

The area-

The area under the line in a velocity-time graph represents the distance travelled. To find the distance travelled in the graph above, we need to find the area of the light-blue triangle and the dark-blue rectangle.

Area of light-blue triangle -
The width of the triangle is 4 seconds and the height is 8 meters per second. To find the area, you use the equation: area of triangle = 1⁄2 × base × height so the area of the light-blue triangle is 1⁄2 × 8 × 4 = 16m. Area of dark-blue rectangle The width of the rectangle is 6 seconds and the height is 8 meters per second. So the area is 8 × 6 = 48m. Area under the whole graph The area of the light-blue triangle plus the area of the dark-blue rectangle is:16 + 48 = 64m.This is the total area under the distance-time graph. This area represents the distance covered.

7 0

3 years ago

What will a spring scale read for the weight of a 57.0-kg woman in an elevator that moves upward with constant speed of 5.0 m/s

Tanzania [10]

The spring scale will read 559 Newton's or 125.7 pounds.

4 0

3 years ago

You measure the power delivered by a battery to be 4.26 W when it is connected in series with two equal resistors. How much powe

gtnhenbr [62]

Answer:

The power delivered by the battery is 17.04 W

Explanation:

Power through a circuit is given as

P = IV ....1

where P is the power

I is the current through the circuit

V is the voltage through the circuit

The voltage in a circuit is given as

V = IR ....2

Let us take the value of each resistor as equal to R

when connected in series, the total resistance will be

$R_{t}$ = R + R = 2R

If we assume constant voltage through the circuit, then from equation 2, the current in this case is

I = V/2R

If the resistors are connected in parallel, then the total resistance will be

$\frac{1}{R_{t} }$ = $\frac{1}{R}$ +

$R_{t}$ = R/2

The current in this case will be increased since the resistance is reduced

I = 2V/R

comparing the two situations, we can see that the current increased when connected in parallel to a ratio of

$\frac{2V}{R}$ ÷ $\frac{V}{2R}$ =

This means that the current increased 4 times

From equation 1, we can see that electrical power is proportional to the current at a constant voltage, therefore, the power will also increase by four times to

P = 4 x 4.26 = 17.04 W

3 0

3 years ago

A football player runs at 8m/s and plows into a 80kg referee standing on the field causing the referee to fly forward at 5m/s. I

madreJ [45]

The topic here is momentum.

When a collision is said to be elastic, it means that the colliding objects now travel at their own new, indivual and distinct velocities, often in different directions.

So we write that as,

(mass of football player x velocity of football player) + (mass of referee x velocity of referee) = (mass of football player x velocity of football player) + (mass of referee x velocity of referee)

(M × 8) + (80 × 0) = (M× 0) + (80 × 5)

8M = 400

M = 50 kg

4 0

3 years ago

Suppose a 1500 kg speed boat is traveling with a velocity of 30 m/s what is the speed boats Monument

DanielleElmas [232]

Answer: 45000kgm/s

Explanation:

Given that:

Mass of speed boat = 1500 kg

Velocity of speedboat = 30 m/s

Speed boats Momentum = ?

The Speed boat momentum is the product of its mass and the velocity by which it moves. Momentum is a vector quantity and measured in kgm/s

i.e Momentum = mass x velocity

= 1500 kg x 30 m/s

= 45000kgm/s

Thus, the speed boats momentum is 45000kgm/s

7 0

3 years ago