Matter either loses or absorbs energy when it changes from one state to another. For example, when matter changes from a liquid to a solid, it loses energy. The opposite happens when matter changes from a solid to a liquid. For a solid to change to a liquid, matter must absorb energy from its surroundings.

4 0

3 years ago

Cars A and B are racing each other along the same straight road in the following manner: Car A has a head start and is a distanc

kumpel [21]

Answer: $\frac{D_A}{v_B-v_A}$

Explanation:

Given

car A had a head start of $D_A$

and it starts at x=0 and t=0

Car B has to travel a distance of $D_A and d_a$

where $d_a$ is the distance travel by car A in time t

distance travel by car A is

$d_a=v_A\times t$

For car B with speed $v_B$

$d_B=D_A+d_a$

$v_B\times t=D_A+v_A\times t$

$t=\frac{D_A}{v_B-v_A}$

7 0

3 years ago

A calorimeter directly measures ______ in order to calculate ______. (1 point)

Aneli [31]

The complete sentence is:

A calorimeter directly measures changes in temperature in order to calculate specific heat.

In fact, the amount of energy acquired/released by a substance is directly proportional to its change in temperature due to the equation

$Q=mC_s \Delta T$

where Q is the amount of energy, m is the mass of the substance, Cs is the specific heat of the substance and $\Delta T$ is the change in temperature. Therefore, by knowing Q, m and by measuring the change in temperature, it is possible to calculate Cs, the specific heat capacity of the substance.

4 0

3 years ago

Read 2 more answers