Why are x-rays and the radiation emitted by radioisotopes called ionizing radiation?

Final answer:

During freefall, the position and velocity of the skydiver increase at a constant rate until reaching terminal velocity. After opening the parachute, the position and velocity decrease to a new terminal velocity. The acceleration is constant during freefall and becomes negative when the parachute slows the skydiver down.

Explanation:

Position vs. Time:

During the first 5 seconds, the skydiver is in freefall and her position increases at a constant rate. After opening the parachute, her position still increases but at a slower rate due to the decrease in terminal velocity. When the parachute slows her down, the position increases at a slower rate again. The position remains constant during the final 3 seconds as the skydiver lands on the ground.

Velocity vs. Time:

During the freefall, the velocity of the skydiver steadily increases until it reaches the terminal velocity of 50 m/s. After opening the parachute, the velocity decreases to the new terminal velocity of 10 m/s. The velocity remains constant until the skydiver lands.

Acceleration vs. Time:

At the start of the jump, the skydiver experiences a constant acceleration due to gravity. After reaching terminal velocity, the acceleration becomes zero since there is no net force acting on the skydiver. When the parachute is opened, the skydiver experiences a negative acceleration due to air resistance, slowing down until the new terminal velocity is reached. The acceleration then becomes zero until the skydiver lands.

Learn more about Skydiver's motion here:

brainly.com/question/20425153

#SPJ1

Answer:

E = 27 J

Explanation:

It is given that,

Mass of a kitten is 1.5 kg

Initially, it was at a height of 1.8 m refrigerator and finally jumps to a 0.9 m height counter.

We need to find the kitten's gravitational  potential energy on top of the counter. Potential energy is possessed due to the position of an object. It can be given by :

g is acceleration due to gravity

So, the kitten's gravitational  potential energy on top of the counter is 27 J.

A) The temperature at the fat-inner fur boundary be so that the bear loses heat at a rate of 51.4W is; T_i = 38.52°C

B) The thickness of the layer contained within the fur so that the bear loses heat at a rate of 51.4 W is; t = 13.41 cm

We are given;

Diameter of sphere; d = 1.6 m

Radius of sphere; r = d/2

r = 1.6/2

r = 0.8 m

Thickness of bear; t = 3.9 cm cm = 0.039 m

Outer surface Temperature of fur; T_h = 2.8 ∘C

Inner surface Temperature of fat;T_f = 30.9 ∘C

Thermal conductivity of fat; K_f = 0.2 W/m⋅k

Thermal conductivity of air; K_a = 0.024 W/m⋅k

A) To find the temperature at the fat-inner fur boundary when heat loss is 51.4 W, we will use the heat current formula;

H = K_f•A(T_f - T_i)/t

Where;

A is area = 4πr²

A = 4π × 0.8²

A = 8.04 m²

T_i is the temperature we are looking for

H is heat loss = 51.4

t is thickness

Making T_i the subject gives;

T_i = (T_f × H × t)/(K_f × A)

T_i = (30.9 × 51.4 × 0.039)/(0.2 × 8.04)

T_i = 38.52°C

B) We want to find the thickness of the layer contained within the fur. Thus, we will use K_a instead of K_f. Let us make t the subject in the heat current formula to get;

t = (K_a•A(T_i - T_h)/H

t = (0.024 × 8.04 × (38.52 - 2.8))/51.4

t = 0.1341 m

t = 13.41 cm

Read more at; brainly.com/question/14548124

Answer:

Explanation:

Using the equation

H = Q/t = k A ( T hot - T cold) / L

where H is the rate of heat loss = 51.4 W, T cold be temperature of the outer surface, A is the surface area of the fat layer which is a model of sphere ( surface area of a sphere ) = 4πr² where diameter = 1.60 m

radius = 1.60 m / 2 = 0.80 m

A = 4 × 3.142 × ( 0.8²) = 8.04352 m²

making T cold subject of the formula

T cold =  T hot -    = 30.9° C - ( 51.4 W × 3.9 × 10⁻² m) / ( 0.2 W/mK × 8.04352 m² ) =  30.9° C - 1.25 ° C = 29.65° C

b) The thickness of air layer for the bear to lose heat t a rate of 51.4 W

thermal conductivity of air is 0.024 W/mK and rearranging the earlier formula

L = = (0.024 W/ m K × 8.04352 m²) ( 29.65° C - 2.8°C) / 51.4 W = 0.101 m = 10.1 m

Final answer:

To calculate velocity in Physics, the two necessary measurements are displacement and time. Velocity is the speed in a specified direction, determined by dividing displacement by time.

Explanation:

In the field of Physics, the two measurements needed to calculate the velocity of an object are displacement and time. Velocity refers to the speed in a given direction and is calculated by dividing displacement (which gives direction information and distance) by the time it takes to move that distance. For example, if an object traveled 100 meters to the north in 20 seconds, the velocity would be 5 meters per second towards the north.

Learn more about Velocity here:

brainly.com/question/17959122

#SPJ3

Answer:

A. Displacement

B. Time

Your Welcome ❤